The religion of the Shiah was founded by a Jew from Yemen called Abdullah bin Saba'. This religion has started with the assassination of the rightly guided Khalifa Uthman and branched into many sections.
Uthman ruled for twelve years. The first six years were marked by internal peace and tranquility, but during the second half of his caliphate a rebellion arose. The Jews and the Magians, taking advantage of dissatisfaction among the people, began conspiring against Uthman, and by publicly airing their complaints and grievances, gained so much sympathy that it became difficult to distinguish friend from foe.
It may seem surprising that a ruler of such vast territories, whose armies were matchless, was unable to deal with these rebels. If Uthman had wished, the rebellion could have been crushed at the very moment it began. But he was reluctant to be the first to shed the blood of Muslims (especially Sahaba), however rebellious they might be. No one would ever expected what happend later. He preferred to reason with them, to persuade them with kindness and generosity. He well remembered hearing the Prophet say, "Once the sword is unsheathed among my followers, it will not be sheathed until the Last Day."
The rebels demanded that he abdicate and some of the Companions advised him to do so. He would gladly have followed this course of action, but again he was bound by a solemn pledge he had given to the Prophet. "Perhaps God will clothe you with a shirt, Uthman" the Prophet had told him once, "and if the people want you to take it off, do not take it off for them." Uthman said to a well-wisher on a day when his house was surrounded by the rebels, "God's Messenger made a covenant with me and I shall show endurance in adhering to it."
After a long siege, the rebels broke into Uthman's house and murdered him. When the first assassin's sword struck Uthman, he was reciting the verse: "Verily, God sufficeth thee; He is the All-Hearing, the All-Knowing" [2:137]
Ali accepted the caliphate very reluctantly. Uthman's murder and the events surrounding it were a symptom, and also became a cause, of civil strife on a large scale. All governors gave the pledge to Ali except Muawiya, the governor of Sham (Great Syria). Muawiya declined to obey until Uthman's blood was avenged. His decision was based on the fact that he is not required to obey the Caliph until he (Ali) is able to enforce the rule of Allah. Muawiya was the cuisine of 'Uthman, so he was the responsible of asking Ali to bring the murderers to trial. The Prophet's widow Aisha also took the position that Ali should first bring the murderers to trial. Due to the chaotic conditions during the last days of Uthman it was very difficult to establish the identity of the murderers, and Ali refused to punish anyone whose guilt was not lawfully proved.
The pretext for the meeting of the armies on the day of the Camel and the day of Siffin was the demand for `Uthman's killers on the part of `A'isha and Mu`awiya, but the winds of war were fanned by the followers of Abdullah bin Saba' the Jew, from inside all three camps until events escaped the control of the Companions. It is related that `Ali, `A'isha , and Mu`awiya often expressed astonishment at the dissension and opposition that surrounded them.
After that some Shia declared Ali as a god. He then burned them alive with fire. After the killing of Abdullah bin Saba', Shia were divided into many new sects. Each one has its own Imam.
The Seveners or Isma'ilis, like all Shiites, believe that the descendants of Muhammad, through his daughter Fatima and her husband Ali the fourth Caliph, are the rightful rulers of the Muslim world. Thus the descendants of Ali are considered infallible and as divinely guided as Muhammad himself. This sect derives its name from Isma'il, the eldest son of the sixth Imam, Jafar as-Sadiq. In 762 CE, Isma'il died before his father, which resulted in bitter disputes of succession. The minority of Shiites regarded the old line of Imams extinct and chose Isma'il's eldest son as the new Imam. Thus they proclaimed a cycle of seven Imams, Ali being the first and Isma'il the seventh, and thus the seventh Imam after his line of Imams would be the Mahdi, or Messiah, or the seventh after him, etc..
The Isma'ilis have usually been small in numbers, but well organised and disciplined. Soon they developed into a cult, borrowing various ideas from Jewish mysticism, Greek philosophy, Babylonian astrology, Christian Gnosticism, etc.., When secular sciences were being employed in the Abbasid Empire, the Isma'ilis were thriving, and managed to recruit a large number of followers, who formed a well organised guerrilla army. By combining their scholarly skills and extraordinary underground network of spies, the Isma'ilis established their anti-Caliph in Egypt during the 10th century. They named his dynasty after Muhammad's daughter, and thus the name Fatimids emerged. In reality they are the dynasty of a Jew called Abdullah bin Qaddah, and that was they were called Abidi too. The Abidi State in Egypt quickly expanded and soon the Isma'ilis controlled western Syria and a large part of North Africa, killing thousands of Muslims. They also built a new capital, Fustat, near the ancient Pyramids, which in a few centuries grew to be the largest city in the Muslim world, under the name of Cairo.
When the Abidi dynasty was destroyed by the Abbasids, the Isma'ilis split into two sub-sects, Tayibiya and Niziriya, named after two Abidi princes. The former sect was soon transformed into a esoteric cult, which moved its activities underground and became invisible. The Niziriya sect transformed itself back into the pre-Abidi Isma'ilism, developing a network of agents and spies all over the Muslim world. The best known organization within the Niziriya was probably the drug-abusing Assassin sect, notorious for assassinations all over the Muslim world. Today, however, the Niziriya sect has turned pacifist and increasingly Westernized.
Out of the Assassin stronghold in Syria, two heterodox sub-sects have survived, the Alawite and the Druze. The Alawite sect is militant and combines radical theories from both Isma'il and Ithna Shia. The Druzes, on the other hand, have until more recently been more pacifistic, waiting for the return of their Mahdi, the psychotic Abidi Caliph al-Hakim, who 'disappeared' when he burned down his capital around 1000 CE. In the 13th century the Druzes closed their sect, and became a distinct tribe or nation. They serve today in the Israeli army against Palestinian Muslims.
The largest sect within Shia is the Ithna or Twelver, which follows the original line of Imams. When the Seveners chose the son of Isma'il to become the Imam, the majority of Shiites chose Isma'ils younger brother, Muza al-Kazim, as the seventh Imam. The Ithna adopt their 'Twelver' name from their belief in the twelfth Imam, Muhammad ibn al-Askari, who 'disappeared' one day and thus became the hidden Mahdi who would return to earth at the end of days. The 'Twelvers' worship their Imams, sometimes as the incarnation of Ali or Hussain. They form the vast majority of Shiites, including most Iranians and almost 50% of the Iraqi nation.
The third largest body in Shia is the Zaydi sect or the Fivers, prevailing in Yemen and among some Bedouin tribes in Saudi-Arabia. The Zaydi sect is more or less the deification of the 7th century Arabian culture, and it fiercely denounces the semi-divinity of Imams, contrary to the Twelver. Their founder was the fifth Imam, Zayd ibn Abidin, who was a rationalist and thus denounced his alleged divinity. The Zaydi Imams are more like Bedouin sheikhs than divine authorities, and thus reject hereditary leadership, and are only visible during warfare.
There are said to be more than 70 small Shia sects all around the world. Probably the best example of these was the Bahai sect, which has been persecuted and refuted as anti-Islamic, but grows fast as a separate religion, basing its doctrines on 'world peace and harmony' and the unity of all religions. The center of the Bahai sect is in Israel!