Kardash was born in Winnipeg and was of Ukrainian Canadian background. Her parents were both active in the Ukrainian Labour-Farmer Temple Association and her father was a Communist organiser. Mary herself was active in the ULFTA's youth movement and worked as a YCL organiser. She was active in the Communist Party's predecessor, the Labor-Progressive Party, before becoming "an important Party worker in Manitoba". Kardash became secretary of the Winnipeg branch of the Canadian-Soviet Friendly Society. She travelled to Moscow in 1949 as part of the Canadian delegation from the Congress of Canadian Women to the Women's International Democratic Federation, a post-war international for Communist bloc country's women's organizations. As one of a group of long-lived Winnipeg communist municipal politicians, after several attempts, Kardash was first elected to the Winnipeg school board in 1960, and she served as a member intermittently until 1986, being elected as a Communist Party of Canada candidate. She supported radical reform and particularly programs to support aboriginal children, notably during a period of Conservative rule in Manitoba from the late 1970s. It was her retirement from the Winnipeg school board in the late 1980s that ended several decades of Communist representation in the city. Mary met her future husband, Bill Kardash, in 1939 and they married in March 1940, later having two children, Ted and Nancy. Bill was also a Communist leader and represented the party in the Legislative Assembly of Manitoba from 1941 to 1958. Mary ran in north Winnipeg as a Communist candidate for the Manitoba legislature in the 1973 provincial election, and for the House of Commons of Canada in the 1974 federal election, but won only a few hundred votes in both attempts. In the 1980s, Mary Kardash courted controversy by questioning the generally accepted account of Ukrainian famine and opposing a proposal that the history of the famine be included in the educational curriculum. The Communist Party acknowledged that many Ukrainians died by famine in the early 1930s, but they and she denied that Joseph Stalin's government was responsible for an act of genocide. In the early 1990s, Mary and Bill Kardash resisted attempts to wind up the Communist Party of Canada. Kardash died in the mid-1990s. The St. Cross Child Care Centre of Winnipeg was renamed the Mary Kardash Child Care Centre in her honour in 1995.
