In the first war, Trajan invaded Dacia by crossing the river Danube with a boat-bridge and inflicted a crushing defeat on the Dacians at the Second Battle of Tapae in 101 AD. The Dacian king Decebalus was forced to sue for peace. Trajan and Decebalus then concluded a peace treaty which was highly favourable to the Romans. The peace agreement required the Dacians to cede some territory to the Romans and to demolish their fortifications. Decebalus' foreign policy was also restricted, as he was prohibited from entering into alliances with other tribes.