Since its founding, Labour has been influenced by socialist ideas, founded by various left wing groups in 1900 including the Fabian Society, the Independent Labour Party, the Social Democratic Federation and the Scottish Labour Party. Despite this, it appears that once in government Labour have not reflected many socialist ideas even though they are often described as being a socialist party.
The first Labour government was that of Ramsay MacDonald in 1924. He was able to pass the Wheatley Housing Act, create unemployment benefits and increase spending on education. These policies are quite left wing but he was unable to do more socialist things such as nationalisation because he led a minority government that only lasted nine months and he would not have wanted to alienate other parties that could prop his government up. In 1929, MacDonald returned as Prime Minister but was not at all socialist, forced to implement spending cuts due to the Wall Street crash. This resulted in him being expelled from the party by Arthur Henderson after forming a national government. This shows that Labour were not socialist in government because they would not have been able to stay in power in both instances if they had been more socialist.
The next Labour government was in 1945 under Clement Attlee. His policies were clearly socialist, implementing Clause IV by nationalising the commanding heights of the economy and the founding of the NHS and the welfare state. Also, Attlee's government began decolonisation, displaying fraternity. However, many Labour members criticised Attlee for not being socialist enough, failing to fully implement Clause IV (as only the commanding heights were nationalised) and the welfare state can be seen as more of a liberal concept, coming from the Bevridge report with Bevridge a Liberal MP. Furthermore, decolonisation can be seen as pragmatic, it would be impossible to pay to maintain such a large empire as well as nationalisation and welfare reforms. Overall, Attlee's government did reflect socialist ideas with them necessary to solve the problems that followed the Second World War.
During the 1950s, Labour shifted away from nationalisation with some such as Crosland seeing nationalisation as no longer popular and Gaitskall aiming to abandon Clause IV and rename the party 'Modern Labour' with both Crosland and Gaitskall preferring social democracy. Despite this, Wilson's leadership can be seen as quite socialist. Unions were influential, steel was renationalised and the creation of a command economy by founding the department of economic affairs are all socialist. He also improved education by beginning comprehensivisation of schools and creating the Open university, both of which can be seen as creating greater equality, a socialist value. However, no attempts other than with steel were made at trying to implement Clause IV and the 'in a place of strife' policy saw him distancing himself from unions. Also, he did not oppose the Vietnam War which goes against the idea of fraternity. Overall, Wilson's governemnts did represent socialist values but not to the extent that Attlee's did.
James Callaghan attempted to improve housing and held a devolution referendum for Scotland but was not in power long enough to see if his polices would be more socialist than this. While in opposition under the leadership of Michael Foot, Labour became its most socialist with the Bennite challenge giving Marxists and Trotskyists in the party greater influence. Policies in 1983 included unilateral nuclear disarmament, withdrawal from NATO and the European Community, greater union powers and the abolition of the House of Lords which all reflect socialist ideas. However, this shows Labour cannot be too socialist while in government with 1983 resulting in a Conservative landslide victory with the manifesto described as 'the longest suicide note…