Abridged from : Shia in islam book
Chapter1
PART I: THE HISTORICAL BACKGROUND OF SHI'ISM
CHAPTER I THE ORIGIN AND GROWTH OF SHI'ISM :
Shi'ism began with a reference made for the first time to the partisans of Ali (shi'ah-i 'Ali), the first leader of the Household of the Prophet, during the lifetime of the Prophet himself.[1] The course of the first manifestation and the later growth of Islam during the twenty-three years of prophecy brought about many conditions which necessitated the appearance of a group such as the Shi'ites among the companions of the Prophet. The Holy Prophet during the first days of his prophecy, when according to the text of the Quran he was commanded to invite his closer relatives to come to his religion,[2] told them clearly that whoever would be the first to accept his invitation would become his successor and inheritor. Ali was the first to step forth and embrace Islam. The Prophet accepted Ali's submission to the faith and thus
fulfilled his promise.[3]
.....