Abu Bakr

Abu Bakr (c.573-634) was a companion and father-in-law to the Prophet Mohammed. Following the death of the Prophet, Abu Bakr became the first Caliph of the Muslim empire, the Rashidun Caliphate that encompassed the Arabian Peninsula. He is also known as Al-Siddiq, "The Truthful."
Abu Bakr was born in Mecca to a wealthy Bedouin family and developed a fondness for camels, which earned him the nickname "Abu Bakr," which means "father of the foal of the camel." When he was ten, he traveled with his father in a caravan to Syria, along with a 12-year-old Mohammad. After Mohammad declared that he was the Messenger of God, Abu Bakr became one of the earliest converts to Islam, bringing many others into the new faith.
In 613, Abu Bakr delivered the first public address calling on people to embrace the new faith of Islam, for which the crowd beat him severely. In 622, Mohammad ordered all Muslims to migrate to Medina, and Abu Bakr was Mohammad's companion on the journey. In Medina, Abu Bakr bought the land where Mohammad constructed the first mosque.
Abu Bakr also participated in many of the early battles between Muslims and the Quraysh of Mecca, and commanded armies during the campaigns in the later years of Mohammad's expansion of his kingdom. Later, he was the First Amir-ul-Hajj in the history of Islam, leading the first pilgrims to Mecca. Following Mohammad's death Abu Bakr was chosen as his successor, the first Caliph.