 After being defeated at the Battles of Viminacium in their homeland, some Avars defected to the Byzantines in 602 but Emperor Maurice decided not to return home as was customary.He maintained his army camp beyond the Danube throughout the winter but the hardship caused the army to revolt, giving the Avars a desperately needed respite and they attempted an invasion of northern Italy in 610.The Byzantine civil war prompted a Persian invasion in the Byzantine–Sasanian War of 602–628 and after 615, the Avars enjoyed a free hand in the undefended Balkans.