Editing First Sea Lord (section)

{{Short description|Professional head of the UK's Royal Navy}}
{{distinguish|text=[[First Lord of the Admiralty]], [[Lord High Admiral of the United Kingdom|Lord High Admiral]], or [[Admiral of the Fleet (United Kingdom)]]}}
{{Use British English|date=January 2013}}
{{Use dmy dates|date=June 2020}}
{{Infobox official post
| post = First Sea Lord and <br />Chief of the Naval Staff
| body = 
| native_name = 
| flag = Flag of Admiral - Royal Navy.svg
| flagsize = 
| flagborder = yes
| flagcaption = [[List of command flags of the Royal Navy#incumbent First Sea Lord|Admiral's command flag]]
| image = Commandant_General_Royal_Marines_2022_(cropped).jpg
| imagesize = 
| alt = 
| incumbent = General [[Gwyn Jenkins|Sir Gwyn Jenkins]]
| acting = no
| incumbentsince = 27 May 2025
| department = [[Ministry of Defence (United Kingdom)|Ministry of Defence]]<br/>[[Royal Navy]]
| style = General
| member_of = [[Defence Council of the United Kingdom|Defence Council]]<br/> [[Admiralty Board (United Kingdom)|Admiralty Board]]<br/>[[Chiefs of Staff Committee]]
| reports_to = [[Chief of the Defence Staff (United Kingdom)|Chief of the Defence Staff]]
| residence = 
| seat = 
| nominator = [[Secretary of State for Defence]]
| appointer = [[Monarchy of the United Kingdom|The Monarch]]
| appointer_qualified = On the advice of the Prime Minister, subject to formal approval by the [[King-in-Council]]
| termlength = Not fixed
| termlength_qualified = typically 3–4 years
| constituting_instrument = 
| precursor = 
| formation = Senior Naval Lord (1689–1771)<br/>First Naval Lord (1771–1904)<br/>First Sea Lord (from 1904)
| first = [[Admiral (Royal Navy)|Admiral]] [[Arthur Herbert, 1st Earl of Torrington|Arthur Herbert]] (as Senior Naval Lord)<br/>[[Admiral of the Fleet (Royal Navy)|Admiral of the Fleet]] Sir [[John Fisher, 1st Baron Fisher|John Fisher]] (as First Sea Lord)
| last = 
| abolished = 
| succession = 
| abbreviation = 1SL/CNS
| unofficial_names = 
| deputy = [[Deputy First Sea Lord]] (1917-1919, 1942-1946)<br/> [[Vice Chief of the Naval Staff (United Kingdom)|Vice Chief of the Naval Staff]] (1941–1946)<br/>[[Deputy Chief of the Naval Staff (United Kingdom)|Deputy Chief of the Naval Staff]]
| salary = 
| website = {{Official|https://www.royalnavy.mod.uk/organisation/our-people/leadership}}
}}
'''First Sea Lord''', officially known as '''First Sea Lord and Chief of the Naval Staff''' ('''1SL/CNS'''), is the title of a statutory position in the [[British Armed Forces]], held by an [[Admiral (Royal Navy)|admiral]] or a [[General (United Kingdom)|general]] of the Royal Marines. As the highest-ranking officer to serve in the [[Royal Navy]], the chief is the principal [[military advisor]] on matters pertaining to the navy and a deputy to the [[Secretary of State for Defence]]. In a separate capacity, the CNS is a member of the [[Chiefs of Staff Committee]] and, thereby, a military advisor to the [[National Security Council (United Kingdom)|National Security Council]], the [[Prime minister of the United Kingdom|prime minister]] and the [[monarchy of the United Kingdom|monarch]]. The First Sea Lord is typically the highest-ranking officer on [[active duty]] of the Royal Navy unless the [[Chief of the Defence Staff (United Kingdom)|Chief of the Defence Staff]] is a naval officer. The post is currently held by General [[Gwyn Jenkins|Sir Gwyn Jenkins]].

Originally titled the "Senior Naval Lord to the Board of Admiralty" when the post was created in 1689,{{sfn|Rodger|1979| p= 34}} the office was re-styled '''First Naval Lord''' in 1771.{{sfn|Rodger|1979| p= 69}} The concept of a professional "First Naval Lord" was introduced in 1805,{{sfn|Thomas|1988|p=31}} and the title of the office was changed to '''First Sea Lord''' on the appointment of Sir [[John Fisher, 1st Baron Fisher|John "Jackie" Fisher]] in 1904. Since 1923, the First Sea Lord has been a member of the Chiefs of Staff Committee; they now sit on the [[Defence Council of the United Kingdom|Defence Council]] and the [[Admiralty Board]].<ref name=firstsealordandchiefofnavalstaff>{{cite web|url=http://www.mod.uk/defenceinternet/aboutdefence/people/chiefsofstaff/firstsealordandchiefofnavalstaff.htm |publisher=MoD |title=People – First Sea Lord and Chief of Naval Staff |archive-url=https://web.archive.org/web/20121122001312/http://www.mod.uk/DefenceInternet/AboutDefence/People/ChiefsOfStaff/FirstSeaLordAndChiefOfNavalStaff.htm |archive-date=22 November 2012 |accessdate= 23 July 2013}}</ref>