Kaloyan, tsar of Bulgaria, had offered the…

Kaloyan, tsar of Bulgaria, had offered the crusaders an alliance against Constantinople, but his offer had been declined, and the new Latin Empire now expresses the intention of conquering all the lands of Constantinople’s former empire and its neighbors.

Having also driven the Magyars from Bulgarian territory, Kaloyan had concluded a treaty earlier in 1204 with Rome that has consolidated Bulgaria's western border by recognizing the authority of the pope, from whom he has received a royal crown.

However, when the patriarch at Constantinople again recognizes the independence of the Bulgarian church, Kaloyan reverts to Orthodoxy.

The Bulgarians remain hostile to the rump Empire based at Nicaea.