The Rashidun army (جيش الراشدين) was the core of the Rashidun Caliphate's armed forces during the early Muslim conquests in the 7th century. The army is reported to have maintained a high level of discipline, strategic prowess and organization, granting them successive victories in their various campaigns.
In its time, the Rashidun army was a very powerful and effective force. The three most successful generals of the army were Khalid ibn al-Walid, who conquered Persian Mesopotamia and the Roman Levant, Abu Ubaidah ibn al-Jarrah, who also conquered parts of the Roman Levant, and Amr ibn al-As, who conquered Roman Egypt. The army was a key component in the Rashidun Caliphate's territorial expansion and served as a medium for the early spread of Islam into the territories it conquered.
Muhammad in Medina
According to Tarikh at Tabari, the nucleus of the early caliphate forces were formed from the Green Division (al-Katibah al-Khadra), a unit that consisted of early converts from Muhajirun and Ansar that marched on to conquer Mecca.
Succession to MuhammadAbu Bakar and Ridda wars
Upon Muhammad's death, the Muslim community was unprepared for the loss of its leader and many experienced a profound shock. Umar was particularly affected, instead declaring that Muhammad had gone to consult with God and would soon return, threatening anyone who would say that Muhammad was dead. Abu Bakr, having returned to Medina, calmed Umar by showing him Muhammad's body, convincing him of his death. He then addressed those who had gathered at the mosque, saying, "If anyone worships Muhammad, Muhammad is dead. If anyone worships God, God is alive, immortal", thus putting an end to any idolising impulse in the population. He then concluded with a verse from the Quran: "Muhammad is no more than an apostle, and many apostles have passed away before him."
Troubles emerged soon after Abu Bakr's succession, with several Arab tribes launching revolts, threatening the unity and stability of the new community and state.