First Lord of the Admiralty

First Lord of the Admiralty, formally the Office of the First Lord of the Admiralty, was the title of the political head of the Naval Service from 1628 to 1964, when the Admiralty, Air Ministry, Ministry of Defence and War Office were merged to form the Ministry of Defence. The holder was the government's senior adviser on all naval affairs, responsible for the direction and control of the Admiralty (them being the pre-eminent member of the Board of Admiralty), the Royal Navy, and the Royal Marines. It was one of the earliest known permanent government posts.

The modern-day equivalent of the office is the Secretary of State for Defence.