The Balts were largely driven to unite by external threats from aggressive German religious orders. In 1202, the Order of the Livonian Brothers of the Sword was established by Albert, the Bishop of Riga, to promote the Christianization and conquest of the Livonians, Curonians, Semigallians, and Estonians near the Gulf of Riga. The Order waged a number of successful campaigns and posed a great danger to the Lithuanian territories. The Order's progress was halted by its defeat at the Battle of Saule in 1236, after which it almost collapsed. The following year, it merged into the Teutonic Knights.