`Abdu’l-Bahá' , born `Abbás , was the eldest son of Bahá'u'lláh and served as head of the Bahá'í Faith from 1892 until 1921. `Abdu’l-Bahá was later canonized as the last of three "central figures" of the religion, along with Bahá'u'lláh and the Báb, and his writings and authenticated talks are regarded as a source of Bahá'í sacred literature.He was born in Tehran to an aristocratic family. At the age of eight his father was imprisoned during a government crackdown on the Bábí Faith and the family's possessions were looted, leaving them in virtual poverty. His father was exiled from their native Iran, and the family went to live in Baghdad, where they stayed for nine years. They were later called by the Ottoman state to Istanbul before going into another period of confinement in Edirne and finally the prison-city of `Akká . `Abdu’l-Bahá remained a political prisoner there until the Young Turk Revolution freed him in 1908 at the age of 64. He then made several journeys to the West to spread the Bahá'í message beyond its middle-eastern roots, but the onset of World War I left him largely confined to Haifa from 1914–1918. The war replaced the openly hostile Ottoman authorities with the British Mandate, who knighted him for his help in averting famine following the war.
In 1892 `Abdu'l-Bahá was appointed in his father's will to be his successor and head of the Bahá'í Faith. He faced opposition from virtually all his family members, but held the loyalty of the great majority of Bahá'ís around the world. His Tablets of the Divine Plan helped galvanize Bahá'ís in North America into spreading the Bahá'í teachings to new territories, and his Will and Testament laid the foundation for the current Bahá'í administrative order. Many of his writings, prayers and letters are extant, and his discourses with the Western Bahá'ís emphasize the growth of the faith by the late 1890s.
`Abdu'l-Bahá's given name was `Abbás. Depending on context, he would have gone by either Mírzá `Abbás or `Abbás Effendi , both of which are equivalent to the English Sir `Abbás. He preferred the title of `Abdu'l-Bahá . He is commonly referred to in Bahá'í texts as "The Master".