half brother of Bahāʾ Ullāh (the founder of the Bahāʾī faith) and leader of his own Bābist movement in the mid-19th century Ottoman Empire.

Yaḥyā was the designated successor of Sayyid Alī Muḥammad, a Shīʿī sectarian leader known as the Bāb (Bāb, the) (Arabic: “gate,” referring to one who has access to the hidden imām). The Bāb was executed in 1850, and by the following year his followers regarded Yaḥyā Mīrzā as the Bāb, in spite of his youth. To avoid persecution by orthodox Shīʿite authorities, he fled Iran in 1853 to Turkish Baghdad where he remained for a decade along with his followers, called Azalis or Bābis. In 1866, in Edirne, a schism erupted between Yaḥyā and Bahāʾ Ullāh, who now claimed to be divine. In order to stop the sectarian strife which erupted among the followers of each, the Ottoman authorities exiled both, sending Yaḥyā to Cyprus in 1868. When Cyprus came under British rule in 1878 he became a pensioner of the crown and lived out his days in obscurity.

Although reviled by the followers of Bahāʾ Ullāh, some, particularly in Iran, still regard Yaḥyā as the true spiritual leader.