Who the started the Muslim religion of Shiite?

Answer 1

Shia started when prophet many times used the term "shia of Ali" and some times said: "O Ali, you and your shias ..."

for example this is one saying of prophet:

"O Ali, you the first who enters Heaven and your shias are in chairs of light and they are happy and their faces are lumine around me. ask God forgive their mistakes and they will be my neighbors in Heaven.

انت اول داخل الجنة من امتی وان شیعتک علی منابر من نور مسرورون مبیضة وجوههم حولی ,اشفع لهم فیکونون غدا فی الجنة جیرانی

this saying is mentioned in many sunni books like these 2 book:

کفایة الطالب، ص135، و در مجمع الزواید ج 9 ص 131

this is only one example prophet used term "shia of Ali" there are many more cases.

shia and sunni have mostly same beliefs and both believe in fundamental beliefs of Islam. today there is up to 260 sect in Islam that are in two category of shia and sunni.

shia believes in Allah, prophet and all fundamentals of Islam.

shia believe after death of prophet God selects the successive for prophet who is the leader of Muslim community and people can not select it.

shia believe the Caliph (Representative of God in earth after prophet) is appointed only by God and can not be selected by people because God said in Koran: "Indeed, I will make upon the earth a successive authority." (Quran 2:30)

this means only God can select an Islamic leader.

in shia they are only fourteen infallible (12 Imams and prophet and his daughter Fatimah Zahra (sa))

and all of them are the same and have no mistake and have the knowledge of everything (this knowledge is from God and by permission of God and is not absolute knowledge. absolute knowledge is only for God and they still do not know many things. but they know anything human may need to know.) and they never die and they hear all sayings and even thinks of all humans after their death by permission of God and they are intermediates between God and human.

and shia Muslims always support them and forgive their lives for them.

shia Muslims do not consider selection of Abubakr as Caliph valid because God did not select him. they believe God ordered prophet to declare Ali is selected as successor of prophet (Quran 5:3) and prophet did this mission in Ghadir event that was in last Hajj of prophet in his life and prophet did a speech for 120,000 Muslims participating that Hajj with prophet. the famous shia book Al-Ghadir is a collection of evidences and proofs for Ghadir Hadith from 100,000 sunni references and read all of 10,000 sunny books. one sunni scholar said if we want to reply Al-Ghadir book (by Allameh Amini) we should first destroy all our books.

Shia doctorin has root in Karbala.