The Complete History (Arabic: الكامل في التاريخ, al-Kāmil fit-Tārīkh), is a classic Islamic history book written by Ali ibn al-Athir. Composed in ca. 1231AD/628AH, it is one of the most important Islamic historical works. Ibn al-Athir was a contemporary and member of the retinue of Salah ad-Din, the Kurdish Muslim general who captured Jerusalem from the Crusaders and Massively reduced European holdings in the Levant, leaving the Principality of Antioch and County of Tripoli much reduced and only a few cities on the coast to the Kingdom of Jerusalem.
The Complete History is organized into volumes, years, and subsections.
The Complete History has several volumes. Each volume is divided in chronological order into years. For example "then the year one and ninety and four hundred began" i.e. 491 AH. Each year has several sections committed to major events, which are not necessarily in chronological order. These subsections may include the deaths, births, and dynastic succession of major states like the Seljuk Turks. Subsections also include major political events, the appearance of groups such as the Franks or the Tatars (Mongols), and major battles like the Siege of Jerusalem (1099).
Ibn Athir's depiction of the Rūs is not primarily ethnological, and not dealing with particular customs or detailed geography. Rather, he accounts for the military significance of the Rūs as a people who raided the Caspian region and, importantly, who served the Byzantine Empire as mercenaries. Several references to the Rūs in the Kāmil are connected with Byzantine military operations. The strategic significance of the Varangians was recognized by the Arabs as early as the time of al-Muqaddasī (ca. 945–1000), who had described the Rūs as "two kinds of Byzantines" (jinsān min ar-Rūmī).