When did Kinshasa become the capital of the independent Congo?

Kinshasa, originally named Léopoldville, became the capital of the newly independent republic in 1960. It was not until 1966 that the city's name was officially changed to Kinshasa.1

While the city had served as the administrative headquarters of the Belgian Congo since 1923, it officially replaced Boma as the capital of the colonial territory in 1926.12