Eventually the Banu Aus and the Banu Khazraj became hostile to each other and by the time of Muhammad's Hijra (emigration) to Medina in 622 AD/1 AH, they had been fighting for 120 years and were the sworn enemies of each other.[19] The Banu Nadir and the Banu Qurayza were allied with the Aus, while the Banu Qaynuqa sided with the Khazraj.[20] They fought a total of four wars.[14]