The first Caliph of Islam. Hazrat Abu Bakr Siddiq's self-sacrificing friendship with the Prophet (PBUH) was rewarded by his name being immortalised in the Qur'an as 'the second of the two'. Hazrat Abu Bakr's short caliphate (632-634) was mostly occupied with Riddah (secession) wars. He was adamant in his insistence on unconditional surrender from the seceders. Within six months his general Khalid bin Walid, reduced the tribes to submission. It was Musaylimah, who had declared himself a Prophet, who gave the most stubborn fight, but was finally defeated by Khalid. Hazart Abu Bakr treated the vanquished mercifully and helped to re-establish peace in the country. Al-Hira, in Iran was conquered in 633 and Palestine in 634. The Greek emperor Herculius was subdued. Hazrat Abu Bakr's daughter Ayisha was the favourite wife of the Prophet (PBUH) and he was given the title of Siddiq because of his faithfulness and true friendship with the Prophet (PBUH). He was buried close to the tomb of Hazart Muhammad (PBUH). Hazrat Abu Bakr Siddiq whose full name was Abu Bakr Abd Allah 'Atiq and who was also known as Abu Quhafa.