Berke left no sons, so Batu's grandson Mengu-Timur was nominated by Kublai and succeeded his uncle Berke. In 1267, Mengu-Timur issued a diploma – jarliq – to exempt Rus' clergy from any taxation and gave to the Genoese and Venice exclusive trading rights in Caffa and Azov. Mengu-Timur ordered the Grand prince of Rus to allow German merchants free travel through his lands. This decree also allowed Novgorod's merchants to travel throughout the Suzdal lands without restraint. Mengu Timur honored his vow: when the Danes and the Livonian Knights attacked Novgorod Republic in 1269, the Khan's great basqaq (darughachi), Amraghan, and many Mongols assisted the Rus' army assembled by the Grand duke Yaroslav. The Germans and the Danes were so cowed that they sent gifts to the Mongols and abandoned the region of Narva.The Mongol Khan's authority extended to all Rus' principalities, and in 1274–75 the census took place in all Rus' cities, including Smolensk and Vitebsk.