‘Alī ibn Abī Tālib (Arabic: علي بن أﺑﻲ طالب) Approximately: March 17, 599 - February 28, 661 was an early Islamic leader, the fourth and last Sunni caliph, and the first Shi'a Imam. Although he had limited political influence during his lifetime, he had vast influence on the developments of events during the time of the early Muslims as a military leader, close companion, cousin and son-in-law of Muhammad. Later, his stature as a foremost authority on the Qur'an, Fiqh (Islamic jurisprudence) and religious thought continues to influence Islamic history. He is among the most influential people in the history of Islam after Muhammad himself, being considered second only to Muhammad in divine guidance by Shi'a Muslims. He is revered by the Sunni Muslims as one of the Four Rightly Guided Caliphs and as a foremost authority in Tafsir (Quranic exegesis) and Islamic jurisprudence.