It was founded in New York in January 1924, under the editorship of James Oneal, as an official organ of the Socialist Party of America. Its editorial line was aligned with the anti-communism of the party's "Old Guard" and of trade union leaders like David Dubinsky.
When the Old Guard left the Socialist Party in 1936, the New Leader became the official organ of their new vehicle, the Social Democratic Federation (SDF). During this period tensions began to arise between Oneal and business manager Sol Levitas, an exiled Russian Menshevik who prioritised anti-communism at the expense of positive social democracy. After Oneal resigned in 1940, the paper established links with the Union for Democratic Action, eventually breaking the connection with the SDF.
By 1951, Irving Brown was arranging free subscriptions in Europe, as a way of subsidising the magazine. On at least three occasions, at around the same time, the CIA's Tom Braden handed sums of around $10,000 directly to Levitas.
- James Oneal - Editor 1924-1940
- Sol Levitas - Editor 1936-1961
- Myron Kolatch - Editor 1961-2006
- Melvin Lasky - Literary Editor 1942-32, Foreign correspondent.
- Daniel Bell - 1941-1944
- Irving Kristol - Contributor 1946-75
- thenewleader.com - Official website.
- Guide to the New LeaderRecords TAM.271, Tamiment Library / Wagner Archives, New York University.
- New Leader records, 1895-2008 (bulk dates, 1924-2006), Columbia University Libraries.
- Myron Kolatch, Who We Are and Where We Came From, newleader.com, 2006.
- Hugh Wilford, The CIA, the British Left and the Cold War: Calling the Tune? Frank Cass, 2003, p.123.
- Hugh Wilford, The CIA, the British Left and the Cold War: Calling the Tune? Frank Cass, 2003, p.124. Cite error: Invalid
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- Harvey A. Levenstein, Communism, Anticommunism and the CIO, Greenwood University Press, 1981, p.108.
- Hugh Wilford, The CIA, the British Left and the Cold War: Calling the Tune? Frank Cass, 2003, p.134.
- Frances Stonor-Saunders, Who Paid the Piper? Granta Books, 1999, p.163.
- Hugh Wilford, The CIA, the British Left and the Cold War: Calling the Tune? Frank Cass, 2003, p.135.
- Myron Kolatch, Between Issues, New Leader, September-October 2009.