The Caribbean island of Barbados has officially removed Queen Elizabeth II as head of state and formally become a parliamentary republic, according to NBC News. A ceremony commemorating the occasion took place just after midnight Tuesday morning – exactly 55 years ago since the country gained independence from Britain.

“It is a monumental step,” said Kristina Hinds, a senior lecturer in political science at the University of the West Indies in eastern Barbados. “I think it is part of the evolution of our independence, and it is certainly long overdue.”

Sandra Mason, a Barbadian who had previously served as governor general, was sworn in as the nation’s first president. Parliament elected Mason to the figurehead role last month. Prime Minister Mia Mottley will continue to oversee governmental affairs.

Prince Charles attended the ceremony in place of his mother, the queen. Barbados-born singer and businesswoman Rihanna also appeared at the event, where she was declared a national hero.

“May you continue to shine like a diamond and bring honor to your nation by your works, by your actions and to do credit wherever you shall go,” Mottley said of Rihanna.

Barbados’s move marks the first time in nearly three decades that a former British colony has officially removed the queen as head of state. The milestone comes nearly 400 years after the British arrived on the Caribbean island in 1627, according to Reuters.

Most Barbadians supported the transition, though some argued that the government failed to directly involve residents in determining what kind of republic would best serve the people of Barbados, according to CNN.