He is appointed by the monarch on the advice of the British government, his role is to act as the de facto head of state.

Prior to 2009, Ascension Island was a dependency of Saint Helena and therefore directly represented by the Governor of Saint Helena.

The St Helena, Ascension and Tristan da Cunha Constitution Order 2009 made Saint Helena, Ascension Island, and Tristan da Cunha, equal constituent parts of the territory with their own governments and established the position of Governor of Ascension.

However, as Ascension Island is 809 miles (1,302 km) away from Saint Helena, an administrator is appointed to act as the Governor's representative on the island specifically.

This arrangement predates the current constitutional structure and the first administrator was appointed in 1942.