Editing History of Iran (section)

===Early Islamic period===
====Islamic conquest of Persia (633–651)====
{{Main|Muslim conquest of Persia}}
[[File:Map of expansion of Caliphate.svg|400px|thumb|Phases of the Islamic conquest {{legend|#a1584e|Expansion under Muhammad, 622–632}} {{legend|#ef9070|Expansion during the Rashidun Caliphate, 632–661}} {{legend|#fad07d|Expansion during the Umayyad Caliphate, 661–750}}]]

In 633, when the Sasanian king [[Yazdegerd III]] was ruling over Iran, the Muslims under [[Umar]] invaded the country right after it had been in a bloody civil war. Several Iranian nobles and families such as king Dinar of the [[House of Karen]], and later [[Kanarang]]iyans of [[Greater Khorasan|Khorasan]], mutinied against their Sasanian overlords. Although the [[House of Mihran]] had claimed the Sasanian throne under the two prominent generals [[Bahrām Chōbin]] and [[Shahrbaraz]], it remained loyal to the Sasanians during their struggle against the Arabs, but the Mihrans were eventually betrayed and defeated by their own kinsmen, the [[House of Ispahbudhan]], under their leader [[Farrukhzad]], who had mutinied against Yazdegerd III.

Yazdegerd III fled from one district to another until a local miller killed him for his purse at [[Merv]] in 651.<ref>{{cite encyclopedia | url=http://p2.www.britannica.com/oscar/print?articleId=106324&fullArticle=true&tocId=9106324 | title=Iran | encyclopedia=[[Encyclopædia Britannica]] | access-date=2007-06-21 | archive-date=2013-08-13 | archive-url=https://web.archive.org/web/20130813184232/http://p2.www.britannica.com/oscar/print?articleId=106324&fullArticle=true&tocId=9106324 | url-status=live }}</ref> By 674, Muslims had conquered [[Greater Khorasan]] (which included modern Iranian Khorasan province and modern Afghanistan and parts of [[Transoxiana]]).

The [[Muslim conquest of Persia]] ended the Sasanian Empire and led to the eventual decline of the [[Zoroastrianism|Zoroastrian]] religion in Persia. Over time, the majority of Iranians converted to Islam. Most of the aspects of the previous Persian civilizations were not discarded but were absorbed by the new [[Islam]]ic polity. As [[Bernard Lewis]] has commented:
{{blockquote|"These events have been variously seen in Iran: by some as a blessing, the advent of the true faith, the end of the age of ignorance and heathenism; by others as a humiliating national defeat, the conquest and subjugation of the country by foreign invaders. Both perceptions are of course valid, depending on one's angle of vision."<ref name="lewis">{{cite web|url=http://www.tau.ac.il/dayancenter/mel/lewis.html |title=Iran in history |first=Bernard |last=Lewis |publisher=[[Tel Aviv University]] |access-date=2007-04-03  |archive-url=https://web.archive.org/web/20070429144545/http://www.tau.ac.il/dayancenter/mel/lewis.html |archive-date=2007-04-29 }}</ref>}}

====Umayyad era and Muslim incursions into the Caspian coast====
{{Main|Umayyad Caliphate}}
After the fall of the Sasanian Empire in 651, the [[Arabs]] of the [[Umayyad Caliphate]] adopted many Persian customs, especially the administrative and the court mannerisms. Arab provincial governors were undoubtedly either Persianized [[Arameans]] or ethnic Persians; certainly Persian remained the language of official business of the caliphate until the adoption of Arabic toward the end of the seventh century,<ref>Hawting G., ''The First Dynasty of Islam. The Umayyad Caliphate AD 661–750'', (London) 1986, pp. 63–64</ref> when in 692 minting began at the capital, [[Damascus]]. The new Islamic coins evolved from imitations of Sasanian coins (as well as [[Byzantine]]), and the [[Pahlavi script]] on the coinage was replaced with [[Arabic alphabet]].

During the Umayyad Caliphate, the Arab conquerors imposed [[Arabic]] as the primary language of the subject peoples throughout their empire. [[Al-Hajjaj ibn Yusuf]], who was not happy with the prevalence of the Persian language in the [[divan]], ordered the official language of the conquered lands to be replaced by Arabic, sometimes by force.<ref>''[[Cambridge History of Iran]]'', by [[Richard Nelson Frye]], [[Abdolhosein Zarrinkoub]], et al. Section on The Arab Conquest of Iran and. Vol 4, 1975. London. p.46</ref> In [[al-Biruni]]'s ''From The Remaining Signs of Past Centuries'' for example it is written:
{{blockquote|"When [[Qutayba ibn Muslim|Qutaibah bin Muslim]] under the command of Al-Hajjaj bin Yousef was sent to [[Khwarezm|Khwarazmia]] with a military expedition and conquered it for the second time, he swiftly killed whoever wrote the Khwarazmian native language that knew of the Khwarazmian heritage, history, and culture. He then killed all their Zoroastrian priests and burned and wasted their books, until gradually the illiterate only remained, who knew nothing of writing, and hence their history was mostly forgotten."<ref>[[Al-Biruni]]. الآثار الباقية عن القرون الخالية, p.35,36,48 وقتی قتبیه بن مسلم سردار حجاج، بار دوم بخوارزم رفت و آن را باز گشود هرکس را که خط خوارزمی می نوشت و از تاریخ و علوم و اخبار گذشته آگاهی داشت از دم تیغ بی دریغ درگذاشت و موبدان و هیربدان قوم را یکسر هلاک نمود و کتابهاشان همه بسوزانید و تباه کرد تا آنکه رفته رفته مردم امی ماندند و از خط و کتابت بی بهره گشتند و اخبار آنها اکثر فراموش شد و از میان رفت</ref>}}

There are a number of historians who see the rule of the Umayyads as setting up the "dhimmah" to increase taxes from the ''[[dhimmi]]s'' to benefit the Muslim Arab community financially and by discouraging conversion.<ref name="Astren">Fred Astren pg.33–35</ref> Governors lodged complaints with the caliph when he enacted laws that made conversion easier, depriving the provinces of revenues.

In the 7th century, when many non-Arabs such as [[Persians]] entered Islam, they were recognized as [[mawla|mawali]] ("clients") and treated as second-class citizens by the ruling Arab elite until the end of the Umayyad Caliphate. During this era, Islam was initially associated with the ethnic identity of the Arab and required formal association with an [[Tribes of Arabia|Arab tribe]] and the adoption of the client status of ''mawali''.<ref name="Astren"/> The half-hearted policies of the late Umayyads to tolerate non-Arab Muslims and Shias had failed to quell unrest among these minorities.

However, all of Iran was still not under Arab control, and the region of [[Daylam]] was under the control of the [[Daylamites]], while [[Tabaristan]] was under [[Dabuyid dynasty|Dabuyid]] and [[Paduspanids|Paduspanid]] control, and the [[Mount Damavand]] region under [[Masmughans of Damavand]]. The Arabs had invaded these regions several times but achieved no decisive result because of the inaccessible terrain of the regions. The most prominent ruler of the Dabuyids, known as [[Farrukhan the Great]] (r. 712–728), managed to hold his domains during his long struggle against the Arab general [[Yazid ibn al-Muhallab]], who was defeated by a combined Dailamite-Dabuyid army, and was forced to retreat from Tabaristan.<ref>Pourshariati (2008), pp. 312–313</ref>

With the death of the Umayyad Caliph [[Hisham ibn Abd al-Malik]] in 743, the Islamic world was launched into civil war. [[Abu Muslim]] was sent to Khorasan by the [[Abbasid Caliphate]] initially as a propagandist and then to revolt on their behalf. He took [[Merv]] defeating the Umayyad governor there [[Nasr ibn Sayyar]]. He became the [[de facto]] Abbasid governor of Khurasan. During the same period, the Dabuyid ruler [[Khurshid of Tabaristan|Khurshid]] declared independence from the Umayyads but was shortly forced to recognize Abbasid authority. In 750, Abu Muslim became the leader of the Abbasid army and defeated the Umayyads at the [[Battle of the Zab]]. Abu Muslim stormed [[Damascus]], the capital of the Umayyad caliphate, later that year.

==== Abbasid period and autonomous Iranian dynasties ====
{{Main|Abbasid Caliphate||Iranian Intermezzo|Tahirid dynasty|Saffarid dynasty|Ziyarid dynasty|Samanids|Sajid dynasty|Sallarid dynasty|Ilyasids|Buyid dynasty|Kakuyids}}
[[File:Saffarids 900ad.jpg|thumb|upright=1.2|The [[Saffarid dynasty]] in 900 AD.]]
[[File:Iran circa 1000AD.png|thumb|upright=1.2|Map of the Iranian dynasties in the mid 10th-century.]]

The Abbasid army consisted primarily of Khorasanians and was led by an Iranian general, [[Abu Muslim Khorasani]]. It contained both Iranian and Arab elements, and the Abbasids enjoyed both Iranian and Arab support. The Abbasids overthrew the Umayyads in 750.<ref name="Islamic Conquest">{{cite web|url=http://www.iranchamber.com/history/islamic_conquest/islamic_conquest.php|title=History of Iran: Islamic Conquest|access-date=2007-06-21|archive-date=2019-10-05|archive-url=https://web.archive.org/web/20191005023220/http://www.iranchamber.com/history/islamic_conquest/islamic_conquest.php|url-status=live}}</ref> According to Amir Arjomand, the [[Abbasid Revolution]] essentially marked the end of the Arab empire and the beginning of a more inclusive, multi-ethnic state in the Middle East.<ref name=said>[[Saïd Amir Arjomand]], Abd Allah Ibn al-Muqaffa and the Abbasid Revolution. [[Iranian Studies (journal)|Iranian Studies]], vol. 27, #1–4. [[London]]: [[Routledge]], 1994. {{JSTOR|i401381}}</ref>

One of the first changes the Abbasids made after taking power from the Umayyads was to move the empire's capital from [[Damascus]], in the [[Levant]], to [[Iraq]]. The latter region was influenced by Persian history and culture, and moving the capital was part of the Persian mawali demand for Arab influence in the empire. The city of [[Baghdad]] was constructed on the [[Tigris River]], in 762, to serve as the new Abbasid capital.<ref name="AHGC">{{cite web|work=Applied History Research Group, University of Calgary |url=https://www.ucalgary.ca/applied_history/tutor/islam/fractured/ |title=The Islamic World to 1600 |access-date=26 August 2006  |archive-url=https://web.archive.org/web/20081005003551/http://www.ucalgary.ca/applied_history/tutor/islam/fractured/ |archive-date=5 October 2008 }}</ref>

The Abbasids established the position of [[vizier]] like [[Barmakids]] in their administration, which was the equivalent of a "vice-caliph", or second-in-command. Eventually, this change meant that many caliphs under the Abbasids ended up in a much more ceremonial role than ever before, with the vizier in real power. A new Persian bureaucracy began to replace the old Arab aristocracy, and the entire administration reflected these changes, demonstrating that the new dynasty was different in many ways from the Umayyads.<ref name="AHGC"/>

By the 9th century, Abbasid control began to wane as regional leaders sprang up in the far corners of the empire to challenge the central authority of the Abbasid caliphate.<ref name="AHGC"/> The Abbasid caliphs began enlisting ''mamluks'', Turkic-speaking warriors, who had been moving out of Central Asia into [[Transoxiana]] as slave warriors as early as the 9th century. Shortly thereafter the real power of the Abbasid caliphs began to wane; eventually, they became religious figureheads while the warrior slaves ruled.<ref name="Islamic Conquest"/>

[[File:Papak Xorramdin.jpg|thumb|upright=.8|[[Babak Khorramdin]] was the leader of ''[[Khurramites|the Khurramīyah movement]]''. A devout [[Zoroaster|Zoroastrian]], he led the Persian freedom movement against oppressive Arab rule.|alt=]]
The 9th century also saw the revolt by native Zoroastrians, known as the [[Khurramites]], against oppressive Arab rule. The movement was led by a Persian freedom fighter [[Babak Khorramdin]]. Babak's Iranianizing<ref>Bernard Lewis (1991), "The Political Language of Islam", University of Chicago Press, pp 482: "Babak's Iranianizing rebellion in Azerbaijan gave occasion for sentiments at the capital to harden against men who were sympathetic to the more explicitly Iranian tradition"</ref> rebellion, from its base in [[Iranian Azerbaijan|Azerbaijan]] in [[Iran|northwestern Iran]],<ref>F. Daftary (1999) Sectarian and National Movements in Iran, Khurasan and Transoxania During Umayyad and Early 'Abbasid Times In History of Civilizations of Central Asia, vol. IV, part One, ed. M. S. Asimov, and C. E. Bosworth. Paris: UNESCO Publishing, pp. 41–60. excerpt from pg 50: "The activities of the Khurammiya reached their peak in the movement of Babak al-Khurrami, whose protracted rebellion based in north-western Iran seriously threatened the stability of the Abbassid caliphate... This revolt lasting for more than twenty years soon spread from Azerbaijan (North/West Iran) to western and central parts of Iran."</ref> called for a return of the political glories of the [[Iranian peoples|Iranian]]<ref>[[Kathryn Babayan]], "Mystics, monarchs, and messiahs", Harvard CMES, 2002. pg 138: "Babak revolted in Azerbaijan (816–838), evoking Abu Muslim as a heroic symbol..and called for a return to the Iranian past"</ref> past. The Khorramdin rebellion of Babak spread to the Western and Central parts of Iran and lasted more than twenty years before it was defeated when Babak was betrayed by [[Afshin (Caliphate General)|Afshin]], a senior general of the Abbasid Caliphate.

As the power of the Abbasid caliphs diminished, a series of dynasties rose in various parts of Iran, some with considerable influence and power. Among the most important of these overlapping dynasties were the [[Tahirids]] in [[Greater Khorasan|Khorasan]] (821–873); the [[Saffarids]] in [[Sistan]] (861–1003, their rule lasted as maliks of Sistan until 1537); and the [[Samanids]] (819–1005), originally at [[Bukhara]]. The Samanids eventually ruled an area from central Iran to Pakistan.<ref name="Islamic Conquest"/>

By the early 10th century, the Abbasids almost lost control to the growing Persian faction known as the [[Buyid dynasty]] (934–1062). Since much of the Abbasid administration had been Persian anyway, the Buyids were quietly able to assume real power in Baghdad. The Buyids were defeated in the mid-11th century by the [[Great Seljuq Empire|Seljuq]] [[Oghuz Turks|Turks]], who continued to exert influence over the Abbasids, while publicly pledging allegiance to them. The balance of power in Baghdad remained as such – with the Abbasids in power in name only – until the Mongol invasion of 1258 sacked the city and definitively ended the Abbasid dynasty.<ref name="AHGC"/>

During the [[Abbasid]] period an enfranchisement was experienced by the ''mawali'' and a shift was made in political conception from that of a primarily Arab empire to one of a Muslim empire<ref name="Tobin">Tobin 113–115</ref> and c. 930 a requirement was enacted that required all bureaucrats of the empire be Muslim.<ref name="Astren" />

====Islamic golden age, Shu'ubiyya movement and Persianization process====
{{See also|Islamization of Iran|Islamic Golden Age|Shu'ubiyya}}
[[File:Ghotb2.jpg|thumb|upright|Extract from a medieval manuscript by [[Qutb al-Din al-Shirazi|Qotbeddin Shirazi]] (1236–1311), a Persian astronomer, depicting an epicyclic planetary model|alt=]]

[[Islamization]] was a long process by which [[Islam]] was gradually adopted by the majority population of Iran. [[Richard Bulliet]]'s "conversion curve" indicates that only about 10% of Iran converted to Islam during the relatively Arab-centric [[Umayyad]] period. Beginning in the [[Abbasid]] period, with its mix of Persian as well as Arab rulers, the Muslim percentage of the population rose. As Persian Muslims consolidated their rule of the country, the Muslim population rose from approximately 40% in the mid-9th century to close to 90% by the end of the 11th century.<ref name="Tobin"/> [[Seyyed Hossein Nasr]] suggests that the rapid increase in conversion was aided by the Persian nationality of the rulers.<ref>Nasr, Hoseyn; Islam and the pliqht of modern man</ref>

Although Persians adopted the religion of their conquerors, over the centuries they worked to protect and revive their distinctive language and culture, a process known as [[Persianization]]. Arabs and Turks participated in this attempt.<ref name="britannica2">''Encyclopædia Britannica'', "Seljuq", Online Edition, ([https://www.britannica.com/eb/article-9066688 LINK] {{Webarchive|url=https://web.archive.org/web/20071219231803/https://www.britannica.com/eb/article-9066688 |date=2007-12-19 }})</ref><ref>Richard Frye, The Heritage of Persia, p. 243.</ref><ref>Rayhanat al- adab, (3rd ed.), vol. 1, p. 181.</ref>

In the 9th and 10th centuries, non-Arab subjects of the [[Ummah]] created a movement called [[Shu'ubiyyah]] in response to the privileged status of Arabs. Most of those behind the movement were Persian, but references to [[Egyptians]], [[Berber people|Berbers]] and [[Aramaeans]] are attested.<ref>Enderwitz, S. "Shu'ubiyya". ''Encyclopedia of Islam''. Vol. IX (1997), pp. 513–14.</ref> Citing as its basis Islamic notions of equality of races and nations, the movement was primarily concerned with preserving Persian culture and protecting Persian identity, though within a Muslim context.

The [[Samanid dynasty]] led the revival of Persian culture and the first important Persian poet after the arrival of Islam, [[Rudaki]], was born during this era and was praised by Samanid kings. The Samanids also revived many ancient Persian festivals. Their successor, the [[Ghaznavids|Ghaznawids]], who were of non-Iranian Turkic origin, also became instrumental in the revival of Persian culture.<ref>{{cite web|url=http://www.iranchamber.com/history/samanids/samanids.php|title=History of Iran: Samanid Dynasty|access-date=2007-06-21|archive-date=2019-04-01|archive-url=https://web.archive.org/web/20190401010449/http://www.iranchamber.com/history/samanids/samanids.php|url-status=live}}</ref>

[[File:A treatise on chess 2.jpg|thumb|upright|Persian manuscript describing how an ambassador from India, probably sent by the [[Maukhari]] King [[Śarvavarman]] of [[Kannauj]], brought [[Shatranj|chess]] to the Persian court of [[Khosrow I]].<ref name="ME">{{cite book |last1=Eder |first1=Manfred A. J. |title=South Asian Archaeology 2007 Proceedings of the 19th Meeting of the European Association of South Asian Archaeology in Ravenna, Italy, July 2007, Volume II |date=2010 |publisher=Archaeopress Archaeology |isbn=978-1-4073-0674-2 |page=69 |url=http://history.chess.free.fr/papers/Eder%202007-2.pdf}}</ref><ref>{{cite book |last1=Bakker |first1=Hans T. |author-link=Hans T. Bakker|title=The Huns in Central and South Asia. How Two Centuries of War against Nomadic Invaders from the Steps are Concluded by a Game of Chess between the Kings of India and Iran |date=2017 |url=https://www.academia.edu/34156496}}</ref>]]

The culmination of the [[Persianization]] movement was the ''[[Shahnameh]]'', the national epic of Iran, written almost entirely in Persian. This voluminous work, reflects Iran's ancient history, its unique cultural values, its pre-Islamic [[Zoroastrian]] religion, and its sense of nationhood. According to [[Bernard Lewis]]:<ref name="lewis"/>

<blockquote>"Iran was indeed Islamized, but it was not Arabized. Persians remained Persians. And after an interval of silence, Iran re-emerged as a separate, different and distinctive element within Islam, eventually adding a new element even to Islam itself. Culturally, politically, and most remarkable of all even religiously, the Iranian contribution to this new Islamic civilization is of immense importance. The work of Iranians can be seen in every field of cultural endeavour, including Arabic poetry, to which poets of Iranian origin composing their poems in Arabic made a very significant contribution. In a sense, Iranian Islam is a second advent of Islam itself, a new Islam sometimes referred to as Islam-i Ajam. It was this Persian Islam, rather than the original Arab Islam, that was brought to new areas and new peoples: to the Turks, first in Central Asia and then in the Middle East in the country which came to be called Turkey, and of course to India. The Ottoman Turks brought a form of Iranian civilization to the walls of Vienna..."</blockquote>

The [[Islamization of Iran]] was to yield deep transformations within the cultural, scientific, and political structure of Iran's society: The blossoming of [[Persian literature]], [[Iranian philosophy|philosophy]], [[Science and technology in Iran|medicine]] and [[Persian art|art]] became major elements of the newly forming Muslim civilization. Inheriting a heritage of thousands of years of civilization, and being at the "crossroads of the major cultural highways",<ref>Caheb C., Cambridge History of Iran, ''Tribes, Cities and Social Organization'', vol. 4, p305–328</ref> contributed to Persia emerging as what culminated into the "[[Islamic Golden Age]]". During this period, [[List of Iranian scientists and scholars|hundreds of scholars and scientists]] vastly contributed to technology, science and medicine, later influencing the rise of European science during [[the Renaissance]].<ref>Kühnel E., in ''Zeitschrift der deutschen morgenländischen Gesell'', Vol. CVI (1956)</ref>

The most important scholars of almost all of the Islamic sects and schools of thought were Persian or lived in Iran, including the most notable and reliable [[Hadith]] collectors of [[Shia]] and [[Sunni]] like [[Shaikh Saduq]], [[Mohammad Ya'qub Kulainy|Shaikh Kulainy]], [[Hakim al-Nishaburi]], [[Muslim ibn al-Hajjaj|Imam Muslim]] and Imam Bukhari, the greatest [[Kalam|theologians]] of Shia and Sunni like [[Shaykh Tusi]], [[Al-Ghazali|Imam Ghazali]], [[Fakhr al-Din al-Razi|Imam Fakhr al-Razi]] and [[Al-Zamakhshari]], the greatest [[physicians]], [[Islamic astronomy|astronomers]], [[Logic in Islamic philosophy|logicians]], [[Islamic mathematics|mathematicians]], [[Metaphysics|metaphysicians]], [[Early Islamic philosophy|philosophers]] and [[Islamic science|scientists]] like [[Avicenna]] and [[Nasīr al-Dīn al-Tūsī]], and the greatest [[Sheikh (Sufism)|shaykhs of Sufism]] like [[Jalal ad-Din Muhammad Rumi|Rumi]] and [[Abdul Qadir Gilani|Abdul-Qadir Gilani]].

===={{anchor|Persianate states and dynasties (977-1219)}}Persianate states and dynasties (977–1219)====
{{Main|Persianate|Ghaznavids|Great Seljuq|Khwarazmian dynasty}}
[[File:Kharaghan.jpg|thumb|The [[Kharraqan towers|Kharaghan twin towers]], built in 1067, Persia, contain tombs of Seljuq princes.]]

In 977, a Turkic governor of the Samanids, [[Sabuktigin]], conquered [[Ghazna]] (in present-day Afghanistan) and established a dynasty, the [[Ghaznavids]], that lasted to 1186.<ref name="Islamic Conquest"/> The Ghaznavid empire grew by taking all of the Samanid territories south of the [[Amu Darya]] in the last decade of the 10th century, and eventually occupied parts of Eastern Iran, Afghanistan, Pakistan and north-west India.<ref name="AHGC"/>

The Ghaznavids are generally credited with launching Islam into a mainly [[Hindu]] India. The invasion of India was undertaken in 1000 by the Ghaznavid ruler, [[Mahmud of Ghazna|Mahmud]], and continued for several years. They were unable to hold power for long, however, particularly after the death of Mahmud in 1030. By 1040 the Seljuqs had taken over the Ghaznavid lands in Iran.<ref name="AHGC"/>

The [[Seljuqs]], who like the Ghaznavids were Persianate in nature and of Turkic origin, slowly conquered Iran over the course of the 11th century.<ref name="Islamic Conquest"/> The dynasty had its origins in the [[Turkoman (ethnonym)|Turcoman]] tribal confederations of Central Asia and marked the beginning of [[Turkic peoples|Turkic]] power in the Middle East. They established a [[Sunni Muslim]] rule over parts of [[Central Asia]] and the Middle East from the 11th to 14th centuries. They set up an empire known as Great Seljuq Empire that stretched from Anatolia in the west to western Afghanistan in the east and the western borders of (modern-day) [[China]] in the north-east; and was the target of the [[First Crusade]]. Today they are regarded as the cultural ancestors of the Western [[Turkish people|Turks]], the present-day inhabitants of [[Turkey]], [[Azerbaijan]] and [[Turkmenistan]], and they are remembered as great patrons of [[Persian culture]], [[Persian art|art]], [[Persian literature|literature]], and [[Persian language|language]].<ref name="britannica3">''[[Encyclopædia Britannica]]'', "Seljuq", Online Edition, ([https://www.britannica.com/eb/article-9066688 LINK] {{Webarchive|url=https://web.archive.org/web/20071219231803/https://www.britannica.com/eb/article-9066688 |date=2007-12-19 }}): ''"... Because the Turkish Seljuqs had no Islamic tradition or strong literary heritage of their own, they adopted the cultural language of their Persian instructors in Islam. Literary Persian thus spread to the whole of Iran, and the Arabic language disappeared in that country except in works of religious scholarship ..."''</ref><ref name="iranica">{{citation
|first= Osman G. | last =Özgüdenli
| date = 20 July 2005
| url = https://iranicaonline.org/articles/persian-manuscripts-1-ottoman
| title= Persian Manuscripts I. in Ottoman and modern Turkish libraries 
| encyclopedia = Encyclopædia Iranica
| archive-url= https://web.archive.org/web/20201205211832/http://www.iranicaonline.org/articles/persian-manuscripts-1-ottoman
| url-status=live 
| archive-date= 5 December 2020
}}</ref><ref name="Ravandi">{{ cite journal
| year=2005
| title= Ravandi, the Seljuq court at Konya and the Persianisation of Anatolian Cities
| journal= Mesogeios (Mediterranean Studies)
| publisher= Editions Herodotos
| volume= 25/26 | pages= 157–169
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}}</ref>

[[File:Seljuk Empire locator map.svg|thumb|300px|Seljuq empire at the time of its greatest extent, at the death of Malik Shah I{{Citation needed|date=November 2009}}|alt=]]

The founder of the dynasty, [[Tughril Beg]], turned his army against the Ghaznavids in Khorasan. He moved south and then west, conquering but not wasting the cities in his path. In 1055 the caliph in Baghdad gave Tughril Beg robes, gifts, and the title King of the East. Under Tughril Beg's successor, [[Malik Shah I|Malik Shah]] (1072–1092), Iran enjoyed a cultural and scientific renaissance, largely attributed to his brilliant Iranian vizier, [[Nizam al Mulk]]. These leaders established the observatory where [[Omar Khayyám]] did much of his experimentation for a new calendar, and they built [[Nizamiyya|religious schools]] in all the major towns. They brought [[Al-Ghazali|Abu Hamid Ghazali]], one of the greatest Islamic theologians, and other eminent scholars to the Seljuq capital at Baghdad and encouraged and supported their work.<ref name="Islamic Conquest"/>

When Malik Shah I died in 1092, the empire split as his brother and four sons quarreled over the apportioning of the empire among themselves. In Anatolia, Malik Shah I was succeeded by [[Kilij Arslan I]] who founded the [[Sultanate of Rûm]] and in Syria by his brother [[Tutush I]]. In Persia he was succeeded by his son [[Mahmud I of Great Seljuq|Mahmud I]] whose reign was contested by his other three brothers [[Barkiyaruq]] in [[Iraq]], [[Muhammad I (Seljuq sultan)|Muhammad I]] in [[Baghdad]] and [[Ahmed Sanjar|Ahmad Sanjar]] in [[Greater Khorasan|Khorasan]]. As Seljuq power in Iran weakened, other dynasties began to step up in its place, including a resurgent Abbasid caliphate and the [[Khwarezmid Empire|Khwarezmshahs]]. The Khwarezmid Empire was a Sunni Muslim Persianate dynasty, of East Turkic origin, that ruled in Central Asia. Originally vassals of the Seljuqs, they took advantage of the decline of the Seljuqs to expand into Iran.<ref>{{cite web|url=http://search.eb.com/eb/article-9045365|title=Academic Home|access-date=2007-06-23|archive-date=2021-03-04|archive-url=https://web.archive.org/web/20210304083325/http://academic.eb.com/|url-status=live}}</ref> In 1194 the Khwarezmshah [[Ala ad-Din Tekish]] defeated the Seljuq sultan [[Toghrul III of Seljuq|Toghrul III]] in battle and the Seljuq empire in Iran collapsed. Of the former Seljuq Empire, only the [[Sultanate of Rum]] in Anatolia remained.

A serious internal threat to the Seljuqs during their reign came from the [[Nizari Ismaili state|Nizari Ismailis]], a secret sect with headquarters at [[Alamut Castle]] between [[Rasht]] and [[Tehran]]. They controlled the immediate area for more than 150 years and sporadically sent out adherents to strengthen their rule by murdering important officials. Several of the various theories on the etymology of the word ''[[assassination|assassin]]'' derive from these killers.<ref name="Islamic Conquest"/>{{clear}}

Parts of northwestern Iran were conquered in the early 13th century AD by the [[Kingdom of Georgia]], led by [[Tamar the Great]].<ref name="Lordkipanidze-154">Lordkipanidze, Mariam (1987), ''Georgia in the XI-XII Centuries''. Tbilisi: Ganatleba, p. 154.</ref>