Editing Viking Age (section)

== Probable causes ==
{{Norse people sidebar}}
{{Main|Viking expansion}}
Many theories are posited for the cause of the Viking invasions; the will to explore likely played a major role. At the time, England, Wales, and Ireland were vulnerable to attack, being divided into many different warring kingdoms in a state of internal disarray, while the Franks were well defended. Overpopulation, especially near the [[Scandinavian Mountains|Scandes]], was a possible reason, although some disagree with this theory.<ref>[https://www.ragweedforge.com/ODIN.html#over Arne Emil Christensen] {{Webarchive |url=https://web.archive.org/web/20160304100440/https://www.ragweedforge.com/ODIN.html#over |date=4 March 2016 }}, ''The Vikings''.</ref> Technological advances like the use of iron and a shortage of women due to selective [[female infanticide]] also likely had an impact.<ref>{{cite book |url=https://www.academia.edu/808691 |title=Selective female infanticide as partial explanation for dearth of women in Viking Age Scandinavia |date=1998 |publisher=Boydell press |isbn=978-0-85115-713-9 |location=Woodbridge |pages=205–221 |last1=Wicker |first1=Nancy |editor1-last=Hallsal |editor1-first=Guy |access-date=15 December 2017 |archive-date=4 October 2023 |archive-url=https://web.archive.org/web/20231004200127/https://www.academia.edu/808691 |url-status=live }}</ref> Tensions caused by Frankish expansion to the south of Scandinavia, and their subsequent attacks upon the Viking peoples, may have also played a role in Viking pillaging.{{Citation needed|date=November 2017}} [[Harald I of Norway]] ("Harald Fairhair") had united Norway around this time and displaced many peoples. As a result, these people sought for new bases to launch counter-raids against Harald.

[[File:Viking Expansion.svg|thumb|upright=1.35|Viking expansion in Europe between the 8th and 11th centuries: The yellow colour includes expansions of the [[Normans]]]]
Debate among scholars is ongoing as to why the Scandinavians began to expand from the eighth through 11th centuries. Various factors have been highlighted: demographic, economic, ideological, political, technological, and environmental models.<ref name="Lund & Sindbæk">{{Cite journal|last1=Lund |first1=Julie |last2=Sindbæk |first2=Søren M. |date=15 May 2021 |title=Crossing the Maelstrom: New Departures in Viking Archaeology |journal=Journal of Archaeological Research |volume=30 |issue=2 |page=172 |language=en |doi=10.1007/s10814-021-09163-3 |issn=1573-7756 |doi-access=free|hdl=10852/89013 |hdl-access=free }}</ref>

===Demographic models===
Barrett considers that prior scholarship having examined causes of the Viking Age in terms of demographic determinism, the resulting explanations have generated a "wide variety of possible models". While admitting that Scandinavia did share in the general European population and settlement expansion at the end of the first millennium, he dismisses 'population pressure' as a realistic cause of the Viking Age.<ref name="Barrett2008">{{cite journal |last1=Barrett |first1=James H. |title=What caused the Viking Age? |journal=Antiquity |date=1 September 2008 |volume=82 |issue=317 |pages=672–673 |doi=10.1017/S0003598X00097301}}</ref> Bagge alludes to the  evidence of demographic growth at the time, manifested in an increase of new settlements, but he declares that a warlike people do not require population pressure to resort to plundering abroad. He grants that although population increase was a factor in this expansion, it was not the incentive for such expeditions.<ref name="Bagge2014">{{cite book |last1=Bagge |first1=Sverre |title=Cross and Scepter: The Rise of the Scandinavian Kingdoms from the Vikings to the Reformation |year=2014 |publisher=Princeton University Press |isbn=978-1-4008-5010-5 |pages=24–25 |url=https://books.google.com/books?id=NFJNAgAAQBAJ&pg=PA25}}</ref> According to Ferguson, the proliferation of the use of iron in Scandinavia at the time increased agricultural yields, allowing for demographic growth that strained the limited capacity of the land.<ref name="Ferguson2009 p. 47">{{cite book |last1=Ferguson |first1=Robert |title=The Vikings: A History |year=2009 |publisher=Penguin |isbn=978-1-101-15142-6 |page=47 |url=https://books.google.com/books?id=HY_klT7NjvAC&pg=PT47}}</ref> As a result, many Scandinavians found themselves with no property and no status. To remedy this, these landless men took to piracy to obtain material wealth. The population continued to grow, and the pirates looked further and further beyond the borders of [[Baltic Sea|the Baltic]], and eventually into all of Europe.<ref>Fletcher, Richard. ''Roman–Britain and Anglo–Saxon England 55 BC–AD 1066''. Mechanicsburg, 2002, 177</ref> Historian [[Anders Winroth]] has also challenged the "overpopulation" thesis, arguing that scholars are "simply repeating an ancient cliché that has no basis in fact."<ref name="Winroth2016">{{cite book |last1=Winroth |first1=Anders |title=The Age of the Vikings |year=2016 |publisher=Princeton University Press |isbn=978-0-691-16929-3 |pages=51–52 |url=https://books.google.com/books?id=E26YDwAAQBAJ&pg=PA51}}</ref>

===Economic model===
The economic model states that the Viking Age was the result of growing urbanism and trade throughout mainland Europe. As the Islamic world grew, so did its trade routes, and the wealth which moved along them was pushed further and further north.<ref>Ferguson, Robert. ''The Vikings: A History''. New York: Viking, 2009. Print., 48 {{ISBN?}}</ref> In Western Europe, proto-urban centres such as those with names ending in ''wich'', the so-called [[-wich town]]s of [[Anglo-Saxon England]], began to boom during the prosperous era known as the "Long Eighth Century".<ref>Hansen, I.L & C. Wickham. ''The Long Eighth Century: Production, Distribution, and Demand.'' Leiden: Brill, 2000. {{ISBN?}}</ref> The Scandinavians, like many other Europeans, were drawn to these wealthier "urban" centres, which soon became frequent targets of Viking raids. The connection of the Scandinavians to larger and richer trade networks lured the Vikings into Western Europe, and soon the rest of Europe and parts of the Middle East. In England, hoards of Viking silver, such as the [[Cuerdale Hoard]] and the [[Vale of York Hoard]], offer insight into this phenomenon. Barrett rejects this model, arguing that the earliest recorded Viking raids were in Western Norway and northern Britain, which were not highly economically integrated areas. He proposes a version of the economic model that points to new economic incentives stemming from a "bulge" in the population of young Scandinavian men, impelling them to engage in maritime activity due to limited economic alternatives.<ref name="Lund & Sindbæk"/>

===Ideological model===
This era coincided with the [[Medieval Warm Period]] (800–1300) and stopped with the start of the [[Little Ice Age]] (about 1250–1850). The start of the Viking Age, with the sack of Lindisfarne, also coincided with [[Charlemagne]]'s [[Saxon Wars]], or Christian wars with pagans in [[Old Saxony|Saxony]]. Bruno Dumézil theorises that the Viking attacks may have been in response to the spread of Christianity among pagan peoples.<ref name="Bruno Dumézil 2005">Bruno Dumézil, master of Conference at Paris X–Nanterre, Normalien, aggregated history, author of conversion and freedom in the barbarian kingdoms. 5th&nbsp;– 8th centuries (Fayard, 2005)</ref><ref name="annals R.20">"Franques Royal Annals" cited in Sawyer, Peter (2001) ''The Oxford Illustrated History of the Vikings''. {{ISBN|0-19-285434-8}}. p. 20</ref><ref name="Decaux 1981 pp. 184">Decaux, Alain and Castelot, André (1981) ''Dictionnaire d'histoire de France''. Perrin. {{ISBN|2-7242-3080-9}}. pp. 184–185</ref><ref name="Boyer, R. 2008 p. 96">Boyer, R. (2008) ''Les Vikings: histoire, mythes, dictionnaire''. R. Laffont. {{ISBN|978-2-221-10631-0}}. p. 96</ref><ref>[[François-Xavier Dillmann]], "Viking civilisation and culture. A bibliography of French-language", Caen, Centre for research on the countries of the North and Northwest, University of Caen, 1975, p. 19, and" Les Vikings&nbsp;– the Scandinavian and European 800–1200 ", 22nd exhibition of art from the Council of Europe, 1992, p. 26</ref> Because of the penetration of [[Christianization of Scandinavia|Christianity in Scandinavia]], serious conflict divided Norway for almost a century.

===Political model===
The first of two main components to the political model is the external "pull" factor, which suggests that the weak political bodies of Britain and Western Europe made for an attractive target for Viking raiders.{{Citation needed|date=March 2018}} The reasons for these weaknesses vary, but generally can be simplified into decentralised polities, or religious sites. As a result, Viking raiders found it easy to sack and then retreat from these areas which were thus frequently raided. The second case is the internal "push" factor, which coincides with a period just before the Viking Age in which Scandinavia was undergoing a mass centralisation of power in the modern-day countries of Denmark, Sweden, and especially Norway. This centralisation of power forced hundreds of chieftains from their lands, which were slowly being appropriated by the kings and dynasties that began to emerge. As a result, many of these chiefs sought refuge elsewhere, and began harrying the coasts of the British Isles and Western Europe.<ref>Barrett, James H. "What Caused the Viking Age?" ''Antiquity'' 82.317 (2008): 671–685 [678–679]</ref> Anders Winroth argues that purposeful choices by warlords "propelled the Viking Age movement of people from Scandinavia."<ref name="Winroth2016"/>

;Technological model: This model suggests that the Viking Age occurred as a result of technological innovations that allowed the Vikings to go on their raids in the first place.<ref>Ferguson, Robert. ''The Vikings: A History''. New York: Viking, 2009. p. 58</ref> There is no doubt that piracy existed in the Baltic before the Viking Age, but developments in sailing technology and practice made it possible for early Viking raiders to attack lands farther away.<ref>Pearson, Andrew. ''Piracy in Late Roman Britain: A Perspective from the Viking Age''. Britannia 37 (2006): Web.</ref><ref name="Bagge2014"/> Among these developments are included the use of larger sails, tacking practices, and 24-hour sailing.<ref name="Barrett2008"/> Anders Winroth writes, "If early medieval Scandinavians had not become exquisite shipwrights, there would have been no Vikings and no Viking Age."<ref name="Winroth2016 72">{{cite book |last1=Winroth |first1=Anders |title=The Age of the Vikings |year=2016 |publisher=Princeton University Press |isbn=978-0-691-16929-3 |page=72 |url=https://books.google.com/books?id=E26YDwAAQBAJ&pg=PA72}}</ref>

These models constitute much of what is known about the motivations for and the causes of the Viking Age. In all likelihood, the beginning of this age was the result of some combination of the aforementioned hypotheses.

The Viking colonisation of islands in the North Atlantic has in part been attributed to a period of favourable climate (the Medieval Climactic Optimum), as the weather was relatively stable and predictable, with calm seas.<ref name=":1">{{Cite book |last=Price |first=T. Douglas |url=https://books.google.com/books?id=gYBJCAAAQBAJ |title=Ancient Scandinavia: An Archaeological History from the First Humans to the Vikings |date=2015 |publisher=Oxford University Press |isbn=978-0-19-023199-6 |pages=321–322 |language=en |access-date=25 July 2021 |archive-date=4 October 2023 |archive-url=https://web.archive.org/web/20231004200130/https://books.google.com/books?id=gYBJCAAAQBAJ |url-status=live }}</ref> [[Sea ice]] was rare, harvests were typically strong, and fishing conditions were good.<ref name=":1" />