Diplomatic career of Muhammad
Muhammad (c. 22 April, 571–11 June, 632) is documented as having engaged as a diplomat during his propagation of Islam and leadership over the growing Muslim Ummah (community). He established a method of communication with other tribal or national leaders through letters, assigned envoys, or by visiting them personally, such as at Ta’if. Instances of written correspondence include letters to Heraclius, the Negus and Khosrau. Although it is likely that Muhammad had initiated contact with other leaders within the Arabian Peninsula, some have questioned whether letters had been sent beyond these boundaries.When Muhammad arrived in Medina in 622, local tribes, mainly the Banu Aus and Banu Khazraj, had been feuding for several decades. Muhammad addressed this by establishing the Constitution of Medina: a document which regulated interactions between the different factions, to which the respective parties agreed. This was a different role for him, as he had remained only a religious figure during his time in Mecca. The result was the eventual formation of a united community in Medina, as well as the political supremacy of Muhammad.Muhammad also participated in agreements and pledges such as ""Pledges of al-`Aqaba"", the Treaty of Hudaybiyyah, and the ""Pledge of the Tree"". He reportedly used a silver seal on letters sent to other notable leaders who were requested to convert to Islam.