Ronnie Ellenblum (; born June 21, 1952,

Haifa Haifa ( ; , ; ) is the List of cities in Israel, third-largest city in Israel—after Jerusalem and Tel Aviv—with a population of in . The city of Haifa forms part of the Haifa metropolitan area, the third-most populous metropolitan area i ...

Israel Israel, officially the State of Israel, is a country in West Asia. It Borders of Israel, shares borders with Lebanon to the north, Syria to the north-east, Jordan to the east, Egypt to the south-west, and the Mediterranean Sea to the west. Isr ...

; died January 7, 2021,

Jerusalem Jerusalem is a city in the Southern Levant, on a plateau in the Judaean Mountains between the Mediterranean Sea, Mediterranean and the Dead Sea. It is one of the List of oldest continuously inhabited cities, oldest cities in the world, and ...

, Israel) was an Israeli professor at the department of

geography Geography (from Ancient Greek ; combining 'Earth' and 'write', literally 'Earth writing') is the study of the lands, features, inhabitants, and phenomena of Earth. Geography is an all-encompassing discipline that seeks an understanding o ...

at the

Hebrew University of Jerusalem The Hebrew University of Jerusalem (HUJI; ) is an Israeli public university, public research university based in Jerusalem. Co-founded by Albert Einstein and Chaim Weizmann in July 1918, the public university officially opened on 1 April 1925. ...

, and a member of the Israel Academy of Sciences and Humanities, specializing in Medieval geographies, the history of the

Levant The Levant ( ) is the subregion that borders the Eastern Mediterranean, Eastern Mediterranean sea to the west, and forms the core of West Asia and the political term, Middle East, ''Middle East''. In its narrowest sense, which is in use toda ...

in the

Middle Ages In the history of Europe, the Middle Ages or medieval period lasted approximately from the 5th to the late 15th centuries, similarly to the post-classical period of global history. It began with the fall of the Western Roman Empire and ...

, and the history of the

Crusades The Crusades were a series of religious wars initiated, supported, and at times directed by the Papacy during the Middle Ages. The most prominent of these were the campaigns to the Holy Land aimed at reclaiming Jerusalem and its surrounding t ...

. His latest studies deal also with environmental and climatic history, the

history of Jerusalem Jerusalem is one of the world's oldest cities, with a history spanning over 5,000 years. Its origins trace back to around 3000 BCE, with the first settlement near the Gihon Spring. The city is first mentioned in Egyptian execration texts arou ...

, and the development of historic cities in general. Ellenblum headed the Vadum Iacob Research Project and was involved in the creation of several databases dealing with the history of Jerusalem (together with al-Quds University); with the maps of Jerusalem and with English translations of documents and charters of the Crusader Period. Ellenblum has developed a comprehensive theoretical approach to 'Fragility,' claiming that a decade or two of climatic disturbance (droughts, untimely rains and severely cold winters) could lead to severe societal effects, and that the amelioration and even stabilization of climatic conditions for several decades can lead to a period of affluence. His theory of Fragility is based on a thorough reading of a wealth of well-dated textual and archaeological evidence, pointing to periods of collapse (in the eastern Mediterranean and northern China during the Medieval Climate Anomaly), and affluence in the entire Mediterranean Basin during the Roman Optimum, and describing these processes yearly, monthly and even daily.

Book publications

* ''Frankish Rural Settlement in the Latin Kingdom of Jerusalem'',

Cambridge University The University of Cambridge is a Public university, public collegiate university, collegiate research university in Cambridge, England. Founded in 1209, the University of Cambridge is the List of oldest universities in continuous operation, wo ...

Press, 1998 * ''Crusader castles and modern histories Cambridge'', Cambridge University Press, 2007 * ''Frankish Castles, Muslim Castles, and the Medieval Citadel of Jerusalem''. In ''In laudem Hierosolymitani: Studies in Crusades and Medieval Culture in Honor of Benjamin Z. Kedar'', edited by Iris Shagrir, Ronnie Ellenblum and Jonathan Riley-Smith. Aldershot: Ashgate, 2007''In laudem Hierosolymitani...''
book excerpts
at Amazon.com. Accessed 26 January 2021. * ''The Collapse of the Eastern Mediterranean: Climate Change and the Decline of the East, 950–1072'', Cambridge University Press, 2012

References

{{DEFAULTSORT:Ellenblum, Ronnie Place of birth missing Israeli geographers Academic staff of the Hebrew University of Jerusalem 21st-century geographers 1952 births 2021 deaths Burials at Har HaMenuchot