A public dispute over who will succeed him now threatens the unity of the Tooro kingdom, following the return of King Oyo's body to Uganda. His coffin landed at Entebbe on Friday, with President Yoweri Museveni among the mourners who came to receive it.

The 34-year-old monarch died in the US last week after treatment for an aggressive form of cancer. He will be buried next Saturday, the day he had hoped to mark the anniversary of his coronation. Uganda has ordered an official burial and national flags will fly at half-mast for three days.

Officials opened a nine-day mourning period for the kingdom. After a short ceremony at Entebbe the casket was flown by military helicopter to Kyegegwa in western Uganda, then driven to the royal palace in Fort Portal. The body will lie in state at Karuziika Palace where the public may pay respects and prayers will be held each evening. A church funeral will precede a traditional procession to the Karambi Royal Tombs, with burial expected to conclude by 14:00 local time, in line with Tooro custom that kings are not buried at night.

King Oyo ascended the throne at age three in 1995 and was crowned when he reached adulthood at 18. Guinness World Records listed him as the world's youngest reigning monarch. He was the 13th monarch of a kingdom founded in the early 19th century and had a reported following of more than two million people.

Parliament held a special tribute where MPs remembered him as a modernising figure who championed education, health and opportunities for young people. Prime Minister Robinah Nabbanja called him a "symbol of unity" and praised his work raising awareness about HIV and Aids among young people. Acting opposition leader Patrick Nsamba Oshabe said, "Heritage and development were never rivals in his hands." President Museveni laid a wreath at the airport.

The king's death has opened an unusually public dispute over succession. He was not officially married, and officials have said he left a young son whose identity will be revealed according to Tooro customs. The kingdom's prime minister, Calvin Armstrong Rwomiire Akiiki, said the monarch had asked that the seriousness of his illness not be disclosed because "he was confident in his recovery," and had hoped to return for Empango on 12 September.

Senior royal figures have publicly differed over the reported heir. Charles Kamurasi, head of the Babiito royal clan, said he had no knowledge of the child, and a royal clan member criticised the prime minister for discussing an heir, saying the matter is "a cultural process" and that the prime minister’s comments were "totally out of order." Akiiki has appealed for the dispute to be resolved privately, warning, "Words spoken in moments of grief can deepen divisions that may take years to repair."

The government has urged restraint and official channels for information. Culture Minister Henry Tumukunde said "The whole world is watching how Uganda mourns its king," and asked people to show "restraint and respect." With royal elders due to meet and legal frameworks for traditional leaders available, the next days will determine whether the succession dispute is settled within custom and law or whether it deepens a public rift as the kingdom concludes its mourning.