Editing Umayyad Caliphate (section)

===Central diwans===
{{Unreferenced section|date=March 2024}}
To assist the caliph in administration there were six boards at the centre: Diwan al-Kharaj (the Board of Revenue), Diwan al-Rasa'il (the Board of Correspondence), Diwan al-Khatam (the Board of Signet), Diwan al-Barid (the Board of Posts), Diwan al-Qudat (the Board of Justice) and Diwan al-Jund (the Military Board).

====Diwan al-Kharaj====
The Central Board of Revenue administered the entire finances of the empire. It also imposed and collected taxes and disbursed revenue.

====Diwan al-Rasa'il====
A regular Board of Correspondence was established under the Umayyads. It issued state missives and circulars to the Central and Provincial Officers. It coordinated the work of all Boards and dealt with all correspondence as the chief secretariat.

====Diwan al-Khatam====
In order to reduce forgery, Diwan al-Khatam (Bureau of Registry), a kind of state chancellery, was instituted by Mu'awiyah. It used to make and preserve a copy of each official document before sealing and dispatching the original to its destination. Thus in the course of time a state archive developed in Damascus by the Umayyads under Abd al-Malik. Under the Umayyads, lead seals bearing Arabic text became an important tool in the construction of a distinct Arab and Muslim political entity and which were critical to the proliferation of the state's Islamic orientation.<ref>{{Cite journal |last=Ramadan |first=Tareq A. |date=2019 |title=Religious Invocations on Umayyad Lead Seals: Evidence of an Emergent Islamic Lexicon |url=https://www.journals.uchicago.edu/doi/abs/10.1086/704439 |journal=University of Chicago. Journal of Near Eastern Studies. |volume=78 |issue=2|pages=273–286 |doi=10.1086/704439 }}</ref>

====Diwan al-Barid====
{{main|Barid}}

Mu'awiyah introduced the postal service, Abd al-Malik extended it throughout his empire, and Walid made full use of it. Umar bin Abdul-Aziz developed it further by building [[caravanserai]]s at stages along the Khurasan highway. Relays of horses were used for the conveyance of dispatches between the caliph and his agents and officials posted in the provinces. The main highways were divided into stages of {{convert|12|mi|km}} each and each stage had horses, donkeys, or camels ready to carry the post. Primarily the service met the needs of government officials, but travelers and their important dispatches were also benefited by the system. The postal carriages were also used for the swift transport of troops. They were able to carry fifty to a hundred men at a time. Under governor [[Yusuf ibn Umar al-Thaqafi]], the postal department of Iraq cost 4,000,000 dirhams a year.

====Diwan al-Qudat====
In the early period of Islam, justice was administered by Muhammad and the orthodox caliphs in person. After the expansion of the Islamic State, Umar al-Faruq had to separate the judiciary from the general administration and appointed the first ''qadi'' in Egypt as early as AD 643/23 AH. After 661, a series of judges served in Egypt during the caliphates of Hisham and Walid II.

====Diwan al-Jund====
The Diwan of Umar, assigning annuities to all Arabs and to the Muslim soldiers of other races, underwent a change in the hands of the Umayyads. The Umayyads meddled with the register and the recipients regarded pensions as the subsistence allowance even without being in active service. Hisham reformed it and paid only to those who participated in the battle.
On the pattern of the Byzantine system, the Umayyads reformed their army organization in general and divided it into five corps: the centre, two wings, vanguards, and rearguards, following the same formation while on the march or on a battlefield. Marwan II (740–50) abandoned the old division and introduced the Kurdus (cohort), a small compact body.
The Umayyad troops were divided into three divisions: infantry, cavalry, and artillery. Arab troops were dressed and armed in Greek fashion. The Umayyad cavalry used plain and round saddles. The artillery used the arradah (ballista), the manjaniq (mangonel), and the dabbabah or kabsh (battering ram). The heavy engines, siege machines, and baggage were carried on camels behind the army.