Kåre Trygve Rein[1] (8 April 1911 – 20 March 1995[2]) was a Norwegian trade unionist.
He was a trade unionist before the war, a secretary in the Union of Employees in Commerce and Offices.
[4] Many years later, Rein claimed that he was ordered to take over as secretary by an armed German, and that he received threats of being arrested for sabotage if he declined.
[6] In March 1945 he became Nazi-installed leader of the Confederation of Trade Unions, succeeding Odd Fossum.
During the legal purge in Norway after World War II he was convicted of treason and in 1947 sentenced to six years of forced labour.