The War raised the profile of the working class and a wish for equality between the classes. Voting was thus extended to include more of the working class. This gave the Labour Party a wider base of appeal and a greater potential number of voters. This gave them the chance to become more influential in Parliament as they may get more MPs voted in.
Labours biggest competition was Liberals as they were connected due to the Lib-Lab Pact and the similarities in the parties often made it hard to see the differences at the fringes. The War divided the Liberals over whether to carry the coalition government on into peacetime. Lloyd George and his coalition won the election but his Liberal Party was split, with Asquith and Lloyd George now on opposing sides. This split made the Party unelectable as they were not joined, and so aided the decline of the Liberal Party as a political contender to government. This allowed the Labour Party to dominate the role once held by the Liberals and helped remove an aspect of their competition. The war had aided the decline of the Liberals which gave way to the rise of Labour.
However, there were mediating factors which laid the foundations for the World War to help the Labour party as it did. Firstly, the Lib-Lab Pact had initiated the crucial first political experience of the party. The two parties had aimed to defeat the Conservatives by both agreeing to put one candidate forward, either from Liberal or Labour, but not both. The other candidate could promote the one standing and thus gain more support. Votes were only split two ways, as opposed to three, and so it was more probable the Conservative candidate would be defeated. This meant Labour gained political seats they would not have gained otherwise. If they had not have had these original seats in Parliament, it is less likely they would have been chosen for the War Cabinet positions. This original political experience was crucial later on and would have stunted their development politically if they had not had it. The Lib-Lab pact laid the foundations for their future political appointments.
The leadership choices were also critical in maintaining the Party which was already weak. The new MPs, such as Ramsay McDonald and Arthur Henderson, were rejected by the Liberals. If they had been accepted, they would not have gone on to join the Labour Party and Henderson would not have been able to keep the party together over their disagreement of the war. The Labour Party disagreed over the war but had joint aims to support the working class. Arthur Henderson managed to prevent the Party splitting as he did not expel any MPs with opposing views so the Party could maintain their unified aim. If he had been accepted by the Liberals, there is a strong chance the Labour Party would have split, meaning the War would have had little affect on their development as they would have been severely weakened by the split.
The reversal of the Osbourne Judgement provided crucial funding for the Party. The Party would not receive funding from land owners as they would not receive anything in return form the Party. The new law meant trade unions could make donations to the Party, giving it a valuable source of money. Without this, the Party would not be able to put candidates up for election and so gain any political experience or influence. The First World War would thus have had little effect as the Party would have had no MPs in Parliament. Funding was essential for developing the Party and gaining it any political influence at all.
In conclusion, the First World War did have a significant influence on the Labour Party. It destroyed class barriers and gave the working class a new importance. Trade unions became essential to influence the working class and the Labour Party was needed to help keep both elements of the side of the government. Many MPs were given places in the War Cabinet and the vote was extended to allow more working class voters. The War also severely damaged the Liberal Party and aided its decline, allowing the Labour Party to fill this place. However, the foundations for this were laid before the War. Initial political experience and good leadership choices allowed the Party to remain united and essential funding meant the Party had the ability to become politically experienced. These factors meant benefits of the War were truly felt by the Labour Party and its developing presence could be further expanded to make it a true political force.
