Bahrain’s Sheikh Khalifa bin Salman al Khalifa, the world’s longest serving Prime Minister who put down Opposition unrest repeatedly during his near half century in power, has died, authorities said on Wednesday.

Sheikh Khalifa, a dominant figure in the Gulf Arab island’s politics, passed away on Wednesday morning at Mayo Clinic hospital in the US, Bahrain’s state news agency said.

Khalifa, 84, the uncle of King Hamad bin Isa al-Khalifa, had served as Prime Minister since the island kingdom declared independence from Britain in 1971. The al-Khalifa family has ruled since 1783.

His stern response to pro-democracy protests in Bahrain in 2011 — and criticism of similar unrest — underlined what for many was the defining characteristic of his career, namely a stalwart defence of dynastic rule.

“The death of the world’s longest serving Prime Minister will be welcomed by many of Bahrain’s political Opposition, as he is regarded as one of the chief architects of an increasingly repressive state,” said Marc Owen Jones, assistant professor of Middle East Studies at Hamad bin Khalifa University in Qatar.