Europeans and the steppe: Russian lands under the Mongol rule

It was endemic on the medieval religious frontier not to admit consciously that one had borrowed institutions from conquered or conquering peoples of a different religion. This was true of Crusader Valencian 13th-century Spain about Islamic Moorish institutions, of the Arab Umayyad dynasty from the 7th century or the Ottoman empire from the 14th century about Byzantine institutions, and of the French Crusader Kingdom of Jerusalem from the 12th century about Islamic institutions (Halperin 2000: 238).