Caliphate of Abu Bakr as-Siddiq

Abu Bakr was elected as the first caliph at the Saqifah of Banu Sa'idah. He immediately faced the crisis of tribes apostatizing and refusing to pay Zakat. He declared: 'By Allah, if they withhold even a goat-rope, I will fight them for it.' Under his leadership, the Riddah Wars reunified Arabia and the Muslim conquests of Iraq and Syria began.