There be reasons but in broader sense he thought Islam is right religion and only way to success in this life as well as hereafter. Just read his interview, you will know the truth.
http://www.soundvision.com/Info/ali/interview.asp
He was hit in the head many times
After winning the championship from Liston in 1964, Clay revealed that he was a member of the Nation of Islam (often called the Black Muslims at the time) and the Nation gave Clay the name Cassius X, discarding his surname as a symbol of his ancestors' enslavement, as had been done by other Nation members. On Friday, March 6, 1964, Malcolm X took Clay on a guided tour of the United Nations building (for a second time). Malcolm X announced that Clay would be granted his "X." That same night, Elijah Muhammad recorded a statement over the phone to be played over the radio that Clay would be renamed Muhammad (one who is worthy of praise) Ali (fourth rightly guided caliph). Only a few journalists (most notably Howard Cosell) accepted it at that time. Venerable boxing announcer Don Dunphy addressed the champion by his adopted name, as did British reporters. The adoption of this name symbolized his new identity as a member of the Nation of Islam. Clay had discovered the Nation during a Golden Gloves tournament in Chicago in 1959, even writing a high school report on the organization. His school teachers at Louisville Central High were alarmed that a youngster with that much potential expressed interest in the nationalist faith. They dissuaded him from becoming involved. Many sportswriters of the early 1960s reported that it was Ali's brother, Rudy Clay, who converted to Islam first (estimating the date as 1962). Others wrote that Clay had been seen at Muslim rallies two years before he fought Liston. Ali's own version is that he did buy a copy of the "Muhammad Speaks" newspaper from a Muslim in Chicago, and a 45 rpm record by Minister Louis X (later Farrakhan) called "A White Man's Heaven is a Black Man's Hell." Aligning himself with the Nation of Islam made him a lightning rod for controversy, turning the outspoken but popular former champion into one of that era's most recognizable and controversial figures. Appearing at rallies with Nation of Islam leader Elijah Muhammad and declaring his allegiance to him at a time when mainstream America viewed them with suspicion - if not outright hostility - made Ali a target of outrage, as well as suspicion. Ali seemed at times to provoke such reactions, with viewpoints that wavered from support for civil rights to outright support of separatism. For example, Ali once stated, in relation to integration: "We who follow the teachings of Elijah Muhammad don't want to be forced to integrate. Integration is wrong. We don't want to live with the white man; that's all."[5] And in relation to inter-racial marriage: "No intelligent black man or black woman in his or her right black mind wants white boys and white girls coming to their homes to marry their black sons and daughters."[6] Indeed, Ali's religious beliefs at the time included the notion that the white man was "the devil" and that white people were not "righteous." Ali claimed that white people hated black people.[7] Ali converted from the Nation of Islam sect to mainstream Sunni Islam in 1975. In a 2004 autobiography, written with daughter Hana Yasmeen Ali, Muhammad Ali attributes his conversion to the shift toward Sunni Islam made by W.D. Muhammad after he gained control of the Nation of Islam upon the death of Elijah Muhammad in 1975.
Muhammad Ali changed his religion because where he lived Americans were treated as second class citizens and because Christianity did not treat black people as equals
Christianity.
Elijah muhammed
Muslim xx
Muhammed Ali
Muhammed Abdul Ali was born in 1951.
Muhammed Ali Kesici is 170 cm.
Mansoor Muhammed Ali Qattaa was born in 1982.
Muhammed Ali Khan Wallajah was born in 1717.
Muhammed Ali Khan Wallajah died in 1795.
I once knew someone close to Ali and he told me Ali was a Muslim before he beat Sonny Liston for the heavyweight championship but didn't declare it to the world until after the fight and announced at that time that he would be known as Muhammed Ali for the rest of time. Guy was one heck of a great fighter and still is one of the most beloved athletes in history.
Mr and Mrs Ali
Ali Muhammed Nasir Mohammed was born on 1982-12-01.