After his crushing victory over Yazdegird and his Persian host at Qadisiya, Khalid ibn al Walid rested in wake of his victory. He was confident of his victory over Persia; it showed that his soldiers were easily capable of getting to grips with the Persians in close quarter combat. However, he was still wary of his other adversaries, the Byzantine Empire - and consequently did not move from his position in the Jezira until peace has been made with Byzantium by the Rashidun Caliph Abu Bakr in 640.