The city was known by various names in history. In the Norse sagas it was  or , meaning city of the Kyivans (from ), which survives in modern Icelandic . Perhaps the earliest original manuscript to name the city is the Kyivan letter, written ca. 930 AD by representatives of the city's Jewish community, with the name written as . In the Byzantine Greek of Constantine Porphyrogenitus's tenth-century ''De Administrando Imperio'' it was , , and "also called Sambatas", . In Arabic, it was  in Al-Istakhri's work of 951 AD, and  according to ibn Rustah and other tenth-century authors. In the medieval Latin of Thietmar of Merseburg's ''Chronicon'' it was mentioned for the year 1015 as . After it was rebuilt in the fifteenth century, Kyiv was called by the Turkic (Crimean Tatar) name  or .