Question: Reginald Fletcher was minister of Civil Aviation under what British Labour politician who served as prime minister of the United Kingdom from 1945 to when?

Context paragraphs:
Ernest Bevin: Ernest Bevin (9 March 1881 – 14 April 1951) was a British statesman, trade union leader, and Labour politician.  He co-founded and served as general secretary of the powerful Transport and General Workers' Union from 1922–40, and as Minister of Labour in the war-time coalition government.  He succeeded in maximizing the British labour supply, for both the armed services and domestic industrial production, with a minimum of strikes and disruption.  His most important role came as Foreign Secretary in the post-war Labour Government, 1945–51.  He gained American financial support, strongly opposed Communism, and aided in the creation of NATO.  Bevin's tenure also saw the end of the Mandate of Palestine and the creation of the State of Israel.  His biographer, Alan Bullock, said that Bevin "stands as the last of the line of foreign secretaries in the tradition created by Castlereagh, Canning and Palmerston in the first half of the 19th century," and that due to the reduction in British power he has no successors.

Reginald Fletcher, 1st Baron Winster: Reginald Thomas Herbert Fletcher, 1st Baron Winster (27 March 1885 – 7 June 1961) was a British Liberal then Labour politician.  He was Minister of Civil Aviation under Clement Attlee between 1945 and 1946 and Governor of Cyprus between 1946 and 1949.

Premiership of Tony Blair: The premiership of Tony Blair began on 2 May 1997 and ended on 27 June 2007.  Whilst serving as Prime Minister of the United Kingdom, Blair concurrently served as the First Lord of the Treasury, the Minister for the Civil Service, the Leader of the Labour Party (until Gordon Brown was declared Labour leader on 24 June 2007), and a member of parliament for the constituency of Sedgefield in County Durham.  He remains a Privy Counsellor having first been appointed in July 1994 when he became Leader of the Opposition.  Tony Blair is the Labour Party's longest-serving Prime Minister, and having led the party to three consecutive general election victories, the only Labour prime minister to serve two full consecutive terms.

Stanley Clinton-Davis, Baron Clinton-Davis: Stanley Clinton Clinton-Davis, Baron Clinton-Davis, PC (born 6 December 1928), born Stanley Clinton Davis, is a British Labour politician, former European Commissioner, former minister and solicitor.  He served as Member of Parliament (MP) for Hackney Central (1970–1983), and was a minister in the Labour governments of Prime Ministers Harold Wilson, James Callaghan and Tony Blair.  He was European Commissioner in the Delors Commission (1985–1989).  In 1990, he became a Life Peer as Baron Clinton-Davis of Hackney, in the London Borough of Hackney, sitting on the Labour benches in the House of Lords, and changed his name to Stanley Clinton-Davis by deed poll.

Clement Attlee: Clement Richard Attlee, 1st Earl Attlee, {'1': ", '2': ", '3': ", '4': "} (3 January 1883 – 8 October 1967) was a British Labour politician who served as Prime Minister of the United Kingdom from 1945 to 1951 and Leader of the Labour Party from 1935 to 1955.  In 1940, Attlee took Labour into the wartime coalition government and served under Winston Churchill, becoming the first person to hold the office of Deputy Prime Minister of the United Kingdom.  He went on to lead the Labour Party to an unexpected landslide victory at the 1945 general election; forming the first Labour majority government, and a mandate to implement its postwar reforms.  The 12.0% national swing from the Conservatives to Labour was unprecedented at that time and remains the largest ever achieved by any party at a general election in British electoral history.  He was re-elected with a narrow majority at the 1950 general election.  In the following year, Attlee called a snap general election, hoping to increase his parliamentary majority.  However, he was narrowly defeated by the Conservatives under the leadership of Winston Churchill; despite winning the most votes of any political party in any general election in British political history until the Conservative Party's fourth consecutive victory in 1992.  Attlee remains the longest-ever serving Leader of the Labour Party.

Jon Trickett: Jon Hedley Trickett (born 2 July 1950) is a British Labour politician who has been the Member of Parliament (MP) for Hemsworth in West Yorkshire since a 1996 by-election.  He served as the Parliamentary Private Secretary to Prime Minister Gordon Brown from 2008 to 2010 and was promoted to the Shadow Cabinet by Ed Miliband in 2011 as Shadow Minister for the Cabinet Office.

Swedish governmental line of succession: The Swedish constitution of 1974 allows the Prime Minister of Sweden to appoint one of the Ministers in the cabinet as Deputy Prime Minister ("biträdande statsminister", also unofficially known as "vice statsminister", "Vice Prime Minister"), in case the Prime Minister for some reason is prevented from performing his or her duties.  However, if a Deputy Prime Minister has not been appointed, the Minister in the cabinet who has served the longest time (and if there are several with equal experience the one who is oldest) takes over as head of government.  Note that the person acting as Prime Minister does not do so on a permanent basis: if a Prime Minister dies, resigns or loses a vote of confidence in the Riksdag, the Speaker of the Riksdag will then confer with the parties of the Riksdag and propose a new Prime Minister, who must be tolerated by a majority of the Riksdag.  If the Prime Minister has resigned or lost a vote of confidence, he or she will remain the head of a government "ad interim" until the new Prime Minister assumes his or her office.  The only case where the governmental line of succession becomes relevant is when the Prime Minister dies (upon which the person next in the line of succession serves as the head of a government "ad interim") or when the Prime Minister is on leave or for any other reason incapable of serving, but still remains in office.  This might be compared to the Presidential line of succession in the United States, where the person next in line assumes the Presidency throughout the remainder of the term if the President dies, resigns or is impeached.

Premiership of Gordon Brown: The premiership of Gordon Brown began on 27 June 2007 when Brown accepted the Queen's invitation to form a government, replacing Tony Blair as the Prime Minister of the United Kingdom.  It ended with his resignation as Prime Minister on 11 May 2010.  While serving as Prime Minister, Brown also served as the First Lord of the Treasury, the Minister for the Civil Service and the Leader of the Labour Party.  He was succeeded as Prime Minister by David Cameron

List of Prime Ministers of the United Kingdom: The Prime Minister of the United Kingdom is the head of the Government of the United Kingdom, and chairs Cabinet meetings.  There is no specific date when the office of Prime Minister first appeared, as the role was not created but rather evolved over a period of time.  The term was used in the House of Commons in 1805 and it was certainly in parliamentary use by the 1880s, and in 1905 the post of Prime Minister was officially given recognition in the order of precedence.  Modern historians generally consider Sir Robert Walpole, who led the government of Great Britain from 1721 to 1742, as the first Prime Minister.  Walpole is also the longest-serving Prime Minister by this definition.  However, Sir Henry Campbell-Bannerman was the first Prime Minister and Margaret Thatcher the longest-serving Prime Minister to have been officially referred to as such.

Hugh Dalton: Edward Hugh John Neale Dalton, Baron Dalton PC (16 August 1887 – 13 February 1962) was a British Labour Party economist and politician who served as Chancellor of the Exchequer from 1945 to 1947.  He shaped Labour Party foreign-policy in the 1930s, opposed pacifism, promoted rearmament against the German threat, and strongly opposed the appeasement policy of Prime Minister Neville Chamberlain in 1938.  He served in Churchill's wartime coalition cabinet.  As Chancellor, he pushed his cheap money policy too hard, and mishandled the sterling crisis of 1947.  Dalton's political position was already in jeopardy in 1947, when, he, seemingly inadvertently, revealed a sentence of the budget to a reporter minutes before delivering his budget speech.  Prime Minister Clement Attlee accepted his resignation, but he later returned to the cabinet in relatively minor positions.

Supporting paragraphs: Reginald Fletcher, 1st Baron Winster Clement Attlee
Answer: 1951