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 Badr him seeing "the camels of [Medina] laden with certain death"). This further demoralized the Quraish, as Arab battles were traditionally low-casualty affairs, and set off another round of bickering among the Quraishi leadership. However, according to Arab traditions Amr ibn Hishām quashed the remaining dissent by appealing to the Quraishi's sense of honor and demanding that they fulfill their blood vengeance. The battle began with champions from both armies emerging to engage in combat. Three of the Medinan Ansar emerged from the Muslim ranks, only to be shouted back by the Meccans, who were nervous about starting any unnecessary feuds