His followers around the world cherished him, while his detractors accused him of brainwashing recruits and extracting money from worshippers.
Moon died this morning at a church-owned hospital near his home in northeast of Seoul, two weeks after being hospitalised with pneumonia, Unification Church spokesman Ahn Ho-yeul said. Moon's wife and children were at his side. He was 92.
Moon founded his Bible-based religion in Seoul in 1954, a year after the Korean War ended, saying Jesus Christ personally called on him to complete his work.
The church gained fame -- and notoriety -- by marrying thousands of followers in mass ceremonies presided over by Moon himself. The couples often came from different countries and had never met, but were matched up by Moon in a bid to build a multicultural religious world.
Today, the Unification Church has 3 million followers, including 100,000 members in the US, and has sent missionaries to 194 countries. But ex-members and critics say the figure is actually no more than 100,000 members worldwide.
The church's holdings include the Washington Times newspaper; the New Yorker Hotel, a midtown Manhattan art deco landmark; and a seafood distribution firm that supplies sushi to Japanese restaurants across the US.
It gave the University of Bridgeport $110m (€87m) over more than a decade to keep the Connecticut school operating.
Jesus
It acquired a ski resort, a professional football team and other businesses in South Korea. It also operates a foreign-owned luxury hotel in North Korea and jointly operates a fledgling North Korean automaker.
The church has been accused of using devious recruitment tactics and duping followers out of money. Parents of followers have expressed worries that their children were brainwashed
into joining.
The church has pointed out that many new religious movements faced similar accusations in their early years.
Moon's followers were often called "Moonies," a term many found pejorative.
Moon was born in 1920 in a rural part of what is today North Korea. He said he was 16 when Jesus Christ first appeared to him and told him to finish the work he had begun on Earth 2,000 years earlier.
Moon, who tried to preach the gospel in the North, was imprisoned there in the late 1940s for alleged spying for South Korea though he disputed the charge.
Divorce
When the Korean War broke out in 1950, he went to South Korea. After divorcing his first wife, he married Hak Ja Han Moon in 1960.
In South Korea, Moon quickly drew young acolytes to his conservative, family-oriented value system and unusual interpretation of the Bible.
He conducted his first mass wedding in Seoul in the early 1960s, and the "blessing ceremonies" grew in scale over the years. A 1982 wedding at New York's Madison Square Garden drew thousands of participants.
"International and intercultural marriages are the quickest way to bring about an ideal world of peace," Moon said in a 2009 autobiography.
"People should marry across national and cultural boundaries with people from countries they consider to be their enemies so that the world of peace can come that much more quickly."
Moon began building a relationship with North Korea in 1991, even meeting with the country's founder, Kim Il Sung.
Moon said he urged Kim to give up his nuclear ambitions, and that Kim responded by saying that his atomic program was for peaceful purposes and he had no intention to use it to "kill my own people".
"The two of us were able to communicate well about our shared hobbies of hunting and fishing," Moon wrote. "At one point, we each felt we had so much to say to the other that we just started talking like old friends meeting after a long separation."
Moon sought and eventually developed a good relationship with conservative American leaders such as former Presidents Richard Nixon, Ronald Reagan and George H.W. Bush.
Yet he also served 13 months at a US federal prison in the mid-1980s after a New York City jury convicted him of filing false tax returns.
In later years, the church adopted a lower profile in the United States and focused on building up its businesses. Moon lived for more than 30 years in the United States, the church said.
As he grew older, Moon also handed over day-to-day control of his empire to his children, but in 2009 he married 45,000 people in simultaneous ceremonies worldwide in his first large-scale mass wedding in years.