Former South Korean President Roh Tae-woo, a decorated war veteran who played a key but difficult role in the country's transition from authoritarian rule to democratic elections, has passed away, according to a Seoul hospital.

The 88-year-old leader died Tuesday, a Seoul National University Hospital representative, who did not give a cause of death, 

Roh had been in bad health since 2002, when he underwent prostate cancer surgery, and he had been hospitalized several times in recent years.

Roh moved from military coup conspirator to South Korea's first democratically elected president in the span of a few decades, only to conclude his political career in ignominy with a prison sentence for treason and corruption.

In 1995, Roh made a heartfelt televised apology to the nation for secretly amassing $654 million in illicit money while in office, saying, "I now feel limitlessly guilty for being a former president."

Roh was born in Talsong County, near the southeastern city of Taegu, on December 4, 1932, the son of a poor farmer. He received his education at the Korean Military Academy in Seoul and afterwards at Fort Bragg, North Carolina, where he studied psychological warfare.

Roh served in the military from 1950 to 1953, and during the Vietnam War, he was the leader of a combat battalion.

When former strongman Park Chung-hee was assassinated in 1979, Roh backed Chun Doo-hwan, a former military classmate, in a military coup that put him in the presidential Blue House. Roh was given a number of government positions as a result of his efforts.

However, a national outcry erupted when Chun named Roh as his successor before of the 1987 presidential elections, with major pro-democracy rallies taking place in Seoul and other cities.

In reaction, and in order to distance himself from Chun, Roh published the "June 29 Declaration," which announced major political reforms, including direct presidential election.

He campaigned as a person for the masses. In office, he dropped the term "excellence" and made the Blue House accessible to the public.

Roh was a global statesman who achieved diplomatic success with his "Nordpolitik" drive to develop formal ties with Cold War adversaries Russia and China.

Roh aided South Korea in forging a new international identity as the driving force behind the 1988 Seoul Olympics. In 1991, he also led the country into the United Nations.