 The Dacian king Decebalus benefited from this, and made out a plan along with the neighboring allied tribes of the Roxolans and Bastarnae, to attack south of the Danube, in the Roman province of Moesia, in an attempt to force the Romans to leave their positions in the mountains near Sarmizegetusa.The Dacian army, together with the Roxolani and the Bastarnae, crossed the frozen Danube but, because the weather was not cold enough, the ice broke under their weight, causing many to die in the frozen water.Trajan moved his army from the mountains, following the Dacians into Moesia.