Bahá'u'lláh, born Mírzá Ḥusayn-`Alí Núrí, was the founder of the Bahá'í Faith. He claimed to be the prophetic fulfilment of Bábism, a 19th-century outgrowth of Shaykhism, and, in a broader sense to be a Manifestation of God. He also claimed he was the fulfillment of the eschatological expectations of Islam, Christianity, and other major religions.
Bahá'u'lláh became a follower of the Báb in Persia in 1845. Three years after the Báb was executed, he was exiled to Baghdad, where in 1863 he proclaimed the Bahá'í Faith when he declared himself He whom God shall make manifest, a messianic figure in Babi theology. Bahá'u'lláh based this announcement on a vision of the Maid of Heaven he claimed to have had while imprisoned in the Síyáh-Chál in Tehran, Persia. He would be further exiled to Edirne and ultimately to the prison city of Acre, Palestine, where he died. He wrote many religious works, most notably the Kitáb-i-Aqdas, the Kitáb-i-Íqán, and the Hidden Words.
Bahá'u'lláh's teachings focus on the unity of God, religion, and mankind. Similar to other monotheistic religions, God is considered the source of all created things. Religion, according to Bahá'u'lláh, is renewed periodically by Manifestations of God, people who are made perfect through divine intervention and whose teachings are the sources of the major world religions throughout history. Bahá'ís view Bahá'u'lláh as the first of these teachers whose mission includes the spiritual unification of the entire planet through the eradication of racism and nationalism. Bahá'u'lláh's teachings include the need for a world tribunal to adjudicate disputes between nations, a uniform system of weights and measures, and an auxiliary language that could be spoken by all the people on earth. Bahá'u'lláh also taught that the cycles of revelatory renewal will continue in the future, with Manifestations of God appearing every thousand years or so.
Bahá'u'lláh's eldest son, `Abdu'l-Bahá, was appointed his successor.