 Leonard "Len" Benker Johnson organized a concert and a rally featuring an American bass singer who became involved with what?
Len Johnson (boxer):  Following the Second World War, he was a co-founder of the New International Society in Manchester, which provided a vehicle for black political and social self-organisation in the city and campaigning against racism at home and abroad, including organising a concert and a rally featuring Paul Robeson in support of the Trenton Six, which were both attended by 10,000 people. Paul Robeson: Paul Leroy Robeson (pronounced ; April 9, 1898 – January 23, 1976) was an American bass singer and actor who became involved with the Civil Rights Movement.
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