Alevism or Alevi (/'ælɛvij/, also /æˈlɛviː/ or /əˈleɪviː/, or /Alevileri, also called as  Qizilbash, Spiritual Shiism or Shī‘ah Imāmī-Tasawwufī Ṭarīqah) is a mystical branch of Islam whose adherents are followers of Ali, the Twelve Imams (other than Sunni Muslims who believe in the four Rashidun caliphs) and their descendant, the 13th century Alevi saint Haji Bektash Veli. Having some links with Twelver Shia Islam (like the importance of the Ahl al-Bayt, the day of Ashura, the Mourning of Muharram, commemorating Karbala, etc.), the practices of the Alevis are based on Sufi elements of the Bektashi tariqa. Alevism is seen as one of the two main branches of Islam in Turkey, the other being Sunni Islam.