The claim made by Herbert Morrison and Hugh Dalton that Morrison was denied the leadership of the Labour Party in the 1935 election by the votes of Labour MPs who were members of a masonic lodge to which Arthur Greenwood belonged has been repeated by several historians, but without
considering the character of the lodge. This article is a detailed examination of the genesis, membership and activities of the lodge in question, New Welcome No. 5139, consecrated in 1929. The documentation relating to the establishment of the lodge claimed that its purpose was to make Freemasonry
more accessible to the working classes, but the pattern of lodge membership suggests that it was intended from the start as a 'class lodge' for Labour MPs and officials which would assist relations between the new Labour government and Freemasonry. Following the formation of the National Government,
the lodge's character changed, and membership eventually became open to all men associated with the Palace of Westminster. It is argued that New Welcome Lodge had little impact on the 1935 leadership election. It is shown that the claim made by the anti-masonic writers Stephen Knight and Martin
Short that Clement Attlee was a freemason misconstrues Dalton's memoirs; no evidence that Attlee was a freemason has ever been found.