Manning welcomed news of the October revolution in Russia, and became a member of the 1917 Club. In peacetime, she became an active speaker on behalf of Labour candidates in elections around the country. She was appointed headmistress of a new experimental Open Air School for undernourished children which Cambridge education authority had established on a farm site, and found this work exceptionally rewarding. In 1929, she served as organising secretary of the National Union of Teachers, becoming its President in 1930. In 1931, she was elected as MP for Islington East in a by-election on 19 February. She did not support Ramsay MacDonald's National Government and stayed in the Labour Party, losing her seat a few months later at the 1931 general election in October. She served on the Labour Party National Executive Committee from 1931 to 1932, and in the 1935 general election unsuccessfully contested Sunderland. She was meanwhile moving away from her previous strict pacifism towards a more active anti-fascism. At the 1936 Labour Party Conference, several party members, including Ellen Wilkinson, Stafford Cripps, Aneurin Bevan and Charles Trevelyan, argued that military help should be given to the Popular Front of Spain, which fought Francisco Franco and his fascistNationalist Army. Despite a passionate appeal from Isabel de Palencia, the Labour Party supported the Conservative Government's policy of non-intervention. Manning disagreed with the official line and became Secretary of the Spanish Medical Aid Committee. In the spring of 1937, she helped to arrange the evacuation of almost 4,000 Basque children to Britain as well as around 200 adults, accompanying the children on the SS Habana. While there she witnessed the bombing of Guernica. In 1938, Manning returned to Spain, where she wrote a report on the hospitals where British doctors and nurses were working. Back in England, she continued to be involved with the Basque children, visiting them and highlighting their plight. Manning was selected as Labour candidate for Epping and won the seat in the 1945 general election. In Parliament, she was known for her commitment to education. Defeated in the 1950 general election, she unsuccessfully contested Epping again in 1951 and 1955.
Last years
Manning was appointed a Dame Commander of the Order of the British Empire in 1966. She remained active in educational work and her autobiography was published in 1970. Her last years, before her death at age 91, were spent in the NUT Home for Retired Teachers at Elstree, England.
Legacy
She was remembered in 2002 by the renaming of a Bilbao square as Plaza de Mrs Leah Manning; a commemorative plaque from the Basque Children of '37 Association was presented to the British House of Commons. A room is named in her honour at Homerton College, Cambridge. A blue plaque was erected to Leah Manning in 2020 on the site of the former ragged school in New Street, Cambridge which is now owned by Anglia Ruskin University and is used as their Institute of Music Therapy. Her work on behalf of the new community Harlow New Town has been commemorated in the name of a day care centre for elderly people in Harlow town park.