2. Devr-i Fâtih Sultan Mehmed Han-ı Sani – 869 AH/1464 AD, In: Mehmed Eşref, Tarih-i umumi ve Osmani atlası, [İstanbul], 1330/. COLL.S/T J.54
Turco-Mongolian nomadic tribes took advantage of the divisions among Rus' princes. 1240 Kyiv fell to the Golden Horde who turned most principalities into its vassals. With khan Öz Beg (1313-'41) their Khanate reached its zenith. He adopted Islam as state religion and transformed inter-factional struggles of the khanate into institutions of his sultanate. On the map left, about the era of Sultan Mehmed the Conqueror, from the Atlas of General and Ottoman History, the Khanate of the Golden Horde is colored grey green. In the 15th century it fell apart into smaller Tatar khanates, like the Crimean Khanate and the Kazakh Khanate. To its west we see in yellow the Grand Duchy of Lithuania, the last state in Central Europe to adopt Christianity. Grand Duke Mindaugas baptism and coronation was recognised by the Pope. In the 14th century this warrior-state annexed the western principalities of Kyivan Rus', hence the name Ruthenia, medieval Latin for Rus' land.