Bani Qurayza
Bani Qurayza was one of the three main Jewish tribes of Medina. When the Prophet arrived at Medina, signed a treaty with Bani Qurayza, but when Ahzab group attacked Medina, Ka’b Ibn Asad –leader of Bani Qurayza- was influenced by one of the chiefs of Bani Nazir, and broke the treaty and joined Quraysh tribe. The Prophet sent Sa’d Ibn Ubada –chief of Khazraj tribe- to Bani Qurayza so as to research about this problem. Sa’d talked to Ka’b Ibn Asad When the siege of Medina (by Arabs) was finally lifted, the Prophet told Muslims to get equipped ####in order to fight aginst Bani Qurayza. The siege of Bani Qurayza lasted for 25 to 30 days, finally the Jews went to the Prophet and asked him to make peace, they asked the Prophet to let them go to Damascus and leave their properties in Medina but the Prophet did not accept and told them to surrender themselves. Eventually they surrendered and chose and S’ad Ibn Mu’adh as the arbitrator. He showed great zeal for the new faith. Sa’d decreed that all the men of Bani Qurayza were to be put to death, the women and children were to be taken captive and their properties were to be shared among Muslims.
Sources :
Islamic encyclopedia
The Prophet’s character