Sam Carr (July 7, 1906–1989) was an organizer for the Communist Party of Canada and, its successor, the Labor-Progressive Party in the 1930s and 1940s. He was born Schmil Kogan in Tomachpol, Ukraine in 1906 and immigrated to Canada in 1924, living in Winnipeg and Regina before settling in Montreal in 1925. Carr became an organizer for the Young Communist League with Fred Rose.

In 1931, Carr was arrested with other Communist Party leaders and detained in Kingston Penitentiary for 30 months for being an officer in the party, which had been initially declared illegal in 1931. Following his release from prison he was an organizer of the 1935 On to Ottawa Trek.

He was the editor of the Communist Party's newspaper, The Clarion, before fleeing to the United States with other party leaders in 1940 when the party was again declared illegal. When the Soviet Union became an ally later in the war as a result of the German invasion of the USSR, those party leaders such as Carr and Tim Buck who had gone underground turned themselves into the authorities in 1942 and were released after ten days on the promise that they would refrain from communist activities. As a result, the Labor-Progressive Party was formed in 1943 as a legal front for the party - Carr became its national organizer.

Frank Frost (April 15, 1936 — October 12, 1999(1999-10-12) (aged 63) was one of the foremost American delta blues harmonica players of his generation.

Born Frank Otis Frost in Auvergne, Arkansas, United States, Frost learned to play piano at church as a young boy. He moved to St. Louis, Missouri at age 15, and spent time as a guitarist with drummer Sam Carr and Carr's father, Robert Nighthawk. He learned to play harmonica from Sonny Boy Williamson, who he toured with.

While playing with guitarist Big Jack Johnson, Frost attracted the interest of the record producer Sam Phillips, founder of Sun Records. Some recordings of note that followed included "Hey Boss Man" and "My Back Scratcher".

In the late 1970s, Frost was re-discovered by a blues enthusiast, Michael Frank, who began releasing albums on his Earwig Music Company label by the trio, now called The Jelly Roll Kings, after a song from Hey Boss Man.

Frost appeared in the films Deep Blues: A Musical Pilgrimage to the Crossroads and Crossroads.