The war had its roots in the ambition of Roman Emperor Justinian to recover the provinces of the former Western Roman Empire, which had been lost to invading barbarian tribes in the previous century (the Migration Period). By the end of the conflict Italy was devastated and considerably depopulated. As a consequence, the victorious Byzantines found themselves unable to resist the invasion of the Lombards in 568, which resulted in the loss of large parts of the Italian peninsula.