Islam migrants ("Muhajirun"), Muhammad in Medina established his political and religious authority. The Constitution of Medina was formulated, instituting a number of rights and responsibilities for the Muslim, Jewish, Christian and pagan communities of Medina, bringing them within the fold of one community—the Ummah. The Constitution established: All the tribes signed the agreement to defend Medina from all external threats and to live in harmony amongst themselves. Within a few years, two battles took place against the Meccan forces: first, the Battle of Badr in 624 – a Muslim victory, and then a year later, when the Meccans returned to Medina,
Battle of the Defile the Turgesh army withdrew north towards Samarkand. The Muslim army followed, and scored a victory in a battle fought near the city. Junayd then retired with his troops to winter in Merv. During the winter, rebellions broke out south of the Oxus, in Tokharistan, which had hitherto been quiescent to Muslim rule. Junayd was forced to set out for Balkh and there dispersed 28,000 of his men to quell the revolt. This left him seriously weakened when, in early 731, the Turgesh laid siege to Samarkand and appeals for aid arrived from the city's governor, Sawra ibn al-Hurr al-Abani. Despite