Marion Meadmore (née Ironquill) grew up on a farm located on Pepeekesis, Saskatchewan. Meadmore is a member of the Cree nation from Saskatchewan and a Residential School Survivor. She later moved to Winnipeg once she got accepted into a pre-medicine course at the University of Manitoba. Meadmore later became an activist, dedicating herself to build a number of local and national organizations that assisted the Indigenous community in a variety of ways.

On June 1958, the Indian and Métis Conference, sponsored by the Community Welfare Planning Council of Greater Winnipeg, made a resolution to establish a referral service for Indian and Métis people. The referral service was to provide guidance and counselling on matters of employment, housing, education, health and other community services. Grants to establish the organization came from three sources: The Winnipeg Foundation, the Manitoba Government, and the Canadian Citizenship Branch of the federal Department of Citizenship and Immigration in Ottawa. Meadmore became part of the Planning Committee that led to the creation of the Indian and Métis Friendship Centre in 1958, located on 376 Donald Street, Winnipeg. Meadmore became the first Aboriginal President of the Board of Directors in 1968 after serving as a Board member for 10 years.
The National Indian Council was formed in 1954 and it became the official organization for both status and non-status Indians in 1961. Meadmore helped organize the conference of the National Indian Council, held in Winnipeg in 1961. The National Indian Council was dissolved in 1968 and replaced with two new national organizations: National Indian Brotherhood and National Métis Union in 1969 and 1970, respectively. The National Indian Brotherhood later became the Assembly of First Nations with Meadmore as the commissioner. The function of the Assembly of First Nations was to represent First Nations and their citizens.

In 1970, Meadmore helped create Kinew Housing, the first non-profit company established under the provisions of the Manitoba Companies Act. Kinew Housing purchased old homes throughout Winnipeg to provide housing for individuals of Aboriginal ancestry to ease the transition of living from rural to urban areas.

Meadmore was the sole founder of Arrowfax Canada Inc. on November 1988. The main purpose of Arrowfax was to create a Native American Directory to create a network of all the Aboriginal people of North, Central and South America. The network was designed to create a bigger market for Aboriginal products and services. Arrowfax was later dissolved on 2004.

Meadmore married Winnipeg Blue Bombers lineman Ron Meadmore and raised three boys. She left Kinew Housing to attend the University of Manitoba Law School. Meadmore became the first Indigenous lawyer in Canada when she graduated in from the University of Manitoba in 1977. After law school, Meadmore opened the first all-female law firm in Winnipeg and practiced law for 10 years. Meadmore received numerous awards for her contributions to society. She was presented with the Order of Canada in 1984, the Golden Jubilee Medal, and the Diamond Jubilee Medal. She also received the Distinguished Alumni Award, Lifetime Achievement awarded by the University of Manitoba in 2015.