Abu Bakr as-Siddiq, also known as Abd Allah ibn Abi Quhafa, was a companion and father-in-law of the Prophet Muhammad. As one of the first people outside Muhammad's family to accept Islam, he was instrumental in spreading the faith among the people of Mecca. In 623 his daughter Aisha was married to Muhammad, strengthening the ties between the two men. Afterwards, he returned to Egypt to continue his missionary work. He died in Pelusium on 23 August 634 and was returned to Medina for burial.