Harry Louis Nathan, 1st Baron Nathan, PC, TD, FBA, FSA (2 February 1889 – 23 October 1963) was a Liberal politician, who later joined the Labour Party.
Nathan was born in London in 1889, son of Michael Henry Nathan, a fine art publisher and Justice of the peace. Educated at St Paul's School, he became a solicitor and member of the firm of Herbert Oppenheimer, Nathan and Vandyk. He became honorary secretary of the Brady Working Lads' Club, the oldest and largest of the London Jewish Lads' Clubs (now JLGB).
Nathan served in World War I, leaving with the rank of Major. He acted as honorary solicitor to the Land and Nation League.
He stood as a Liberal without success in the 1924 general election for Whitechapel and St. George's. He was first elected in 1929 as Member of Parliament (MP) for Bethnal Green North East and was re-elected in 1931. Along with many other Anglo-Jewish communal leaders, Nathan was a founding member of the Central British Fund for German Jewry (now World Jewish Relief). In 1934, he defected to the Labour Party. Although Labour won the seat at the 1935 general election, Nathan was not their candidate, opting instead to stand in Cardiff South. He lost by just 541 votes.