King Oyo Nyimba Kabamba Iguru Rukidi IV, the monarch of Uganda’s Tooro Kingdom who became the world’s youngest reigning king after ascending the throne at the age of three, has died aged 34.

Oyo died on Thursday, according to the Prime Minister of the Tooro Kingdom, Calvin Armstrong Rwomiire Akiiki, who announced his death on Friday.

The cause of death was not immediately disclosed. However, Ugandan media reported that the monarch had been critically ill and was receiving medical treatment in the United States.

Announcing his death, Akiiki described the passing as an “immeasurable loss” to the royal family and the people of Tooro.

He called on the people of the kingdom to remain united, calm and prayerful during the period of mourning.

Oyo became king in 1995 following the death of his father, King Patrick Matthew Kaboyo Rukidi III. He was only three years old at the time, prompting the establishment of a regency to oversee the kingdom until he reached adulthood.

He was formally crowned in 2010 at the age of 18.

Guinness World Records recognised Oyo as the world’s youngest reigning monarch, a distinction he earned after inheriting the throne as a toddler.

The Tooro Kingdom, also known as Toro, is one of Uganda’s traditional kingdoms. While the country is governed by an elected president and traditional kingdoms have no constitutional political authority, they continue to play an important cultural role.

Oyo was the 13th monarch of Tooro, a kingdom founded in the early 19th century. During his 31-year reign, he became a prominent cultural figure and supported causes including youth empowerment, education, climate conservation and HIV/AIDS awareness, according to Uganda’s Daily Monitor.

Succession assured

Despite Oyo not being officially married, the Tooro Kingdom said the royal succession would continue.

Akiiki said the late monarch left behind a son who would serve as his heir, although the child’s identity would be formally announced at the appropriate time in line with Tooro traditions and customs.

“The continuity of the Crown is assured,” the prime minister said.

Tributes followed the announcement from other traditional institutions in Uganda, including the Buganda Kingdom, the country’s largest and most influential traditional institution.

Oyo’s death marks the end of an unusual royal journey that began when he inherited the throne as a three-year-old and continued through his adulthood, making him one of Uganda’s best-known traditional rulers.