The term Sea Lord is one the UK assigns to the most senior personnel in the Royal Navy.
But where does the term originate and how has the Sea Lord role changed over time?
The role also makes the head of the Navy a member of the Defence Council and the Chiefs of Staff Committee.
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On 10 August 1904, the term Sea Lord was coined by the Royal Navy – having previously used the title Naval Lord.
The last First Naval Lord was Lord Walter Kerr who was replaced by the first First Sea Lord Admiral John Fisher.
Adm Fisher was responsible for a number of British Naval innovations, including using oil for fuel instead of coal, developing gunnery and the creation of the Dreadnought battleship.
Currently, the Royal Navy only has two Sea Lords – Admiral Ben Key, the First Sea Lord (1SL) and head of the Navy, and Vice Admiral Martin Connell, the Second Sea Lord (2SL).
The First Sea Lord, the professional head of the Royal Navy, works with the Defence Secretary to ensure the service's fighting capabilities, effectiveness and efficiency, as well as advising on maritime strategy and policy.
The Second Sea Lord is responsible for overseeing all 'people matters' in the Royal Navy – recruiting, training, sport, diversity, welfare and support for families – as well as bases and facilities.
The 2SL reports to the 1SL and is appointed by the Prime Minister.