Shi'a Islam, also known as Shi'ite Islam or Shi'ism, is the second largest branch of Islam after Sunni Islam. From a political viewpoint the history of the Shia was in several stages. The first part was the emergence of the Shia, which starts after Muhammad's death in 632 and lasts until Battle of Karbala in 680. Shia Islam has been divided into three main groupings: Twelvers, Ismailis and Zaidis, with Twelver Shia being the largest and most influential group among Shia.