His body had been lying in state since being flown from Beijing where after a tumultuous life of triumph and tragedy he succumbed Oct. 15 to a heart attack at the age of 89.
Following a procession through the streets of Phnom Penh Friday, his body was placed inside a temple-like, 15-storey high crematorium where his son King Norodom Sihamoni and Queen Mother Norodom Monineath will light the funeral pyre.
In recent days, the capital has witnessed elaborate funeral rites, mingling Hindu, Buddhist and animist traditions, last seen 53 years ago with the death of Sihanouk's father, King Norodom Suramarit. And they may never be seen again in a rapidly modernizing country where monarchy has lost much of its power and glamor.
Thousands of people from across Cambodia have flocked to Phnom Penh in recent weeks to pay their last respects to someone they call the "King-Father."
Earlier official estimates said the mourners Monday would exceed 1 million.
"I don't have any words to express the sorrow and suffering I feel when knowing his body will soon disappear," said a weeping, 79-year-old woman, Hin Mal, from the southern province of Takeo. "I love and respect King Sihanouk
The cremation will climax seven days of official mourning for Sihanouk, who was placed on the throne by the French as a teenager. Instead of proving the puppet the colonials had hoped for, Sihanouk went on to win independence, then rule the country both as monarch and head of state until ousted in a 1970 coup.
A charismatic figure regarded as a "God-King" by many of his subjects, a prideful Sihanouk sided with the Khmer Rouge against the U.S.-backed government but after the victory of the ultra-communists in 1975, he and his wife were held prisoners in the palace. Five of his children died during their reign of terror.
A consummate survivor, Sihanouk emerged as a leader of an insurgency fighting a Phnom Penh government installed by the Vietnamese and went on to broker a peace accord that enabled his return to the throne in 1993. He abdicated 11 years later in favor of Sihamoni, a former ballet dancer who had spent most of his life in European artistic circles and has proved a low-key constitutional monarch overshadowed by strongman Prime Minister Hun Sen.
Sihanouk's dark side, particularly his cooperation with the Khmer Rouge and his often brutal suppression of dissent, has been publicly ignored as loudspeakers broadcast eulogies and television stations show old clips of Sihanouk's triumphs and ebullient personality.
A larger-than-life character, Sihanouk directed films, composed music and led his own jazz band and palace soccer team. His appetite extended to fast cars, food and women, marrying at least five times, some say six, and fathering 14 children.
In coming days, some of Sihanouk's ashes will be scattered near the confluence of the four rivers in Phnom Penh while others will be placed in an urn which, according to his wishes, will be placed on the grounds of the Royal Palace near those of his favorite daughter, Kunthea Buppha, who died at the age of three.
The funeral is being attended by French Prime Minister Jean-Marc Ayrault, Prince Akishino of Japan, leaders of neighboring countries and China's Jia Qinglin, a senior government adviser and former high-ranking Politburo member.
Representing the United States is Ambassador William E. Todd. The U.S. Embassy did not directly respond to explain such a relatively low-level representation given the long U.S. involvement in Cambodia.
Many Cambodians were upset when U.S. President Barack Obama was one of the only leaders attending a regional summit here in November not to pay his respects before Sihanouk's body. The president had a reportedly tense meeting with Hun Sen at the time, with Obama pressing him on Cambodia's worsening human rights record.
Associated Press reporter Sopheng Cheang in Phnom Penh contributed to his report.