In 1243 he was obliged to cede to Venice, Zara, a perpetual apple of discord between the two states; but he kept his hold upon Spalato and his other Dalmatian possessions, and his wise policy of religious tolerance in Bosnia enabled Hungary to rule that province peaceably for many years.
After the capture of Zara, however, he joined the crusaders, and played a great part in all the events which followed till the capture of Constantinople by the Latins in 1204.
By 1102, however, Zara, Trail, Spalato and all the islands as far as the Cetina were in his hands.
But Zara and Dalmatia had revolted from Venice in 1166 and were as yet unsubdued.
Zara was recovered, and while still at Zara the leaders of the Crusade, supported by Dandolo, resolved for their own private purposes to attack Constantinople, instead of making for the Holy Land.