Charles Grant Marshall was born in Winnipeg on December 23, 1931. He graduated high school at West Kildonan Collegiate in 1948 and received the Governor General's Medal. Marshall's first love of fashion and costume design was not available for study in Canada at that time so he decided on his second choice, interior design.
Upon graduating from the University of Manitoba in 1955, with the Gold Medal, Marshall went on to teach at the faculty, serving as head of the department from 1989 until 1994. He loved teaching and was a well-liked professor at the Faculty of Interior Design. He was a founding member of the Interior Designers of Canada Foundation, and was later made a Fellow of the Professional Interior Designers of Winnipeg. Amongst his several awards and accolades he was particularly proud of his receipt of the University of Manitoba Alumni Jubilee Award (1980), and the Manitoba Premier's Award of Excellence for Interior Design, for his work on the Anne Ross Daycare Centre (1985). Marshall's first design practice, Design Associates later became Grant Marshall Interiors Limited. He designed thousands of beautiful residential interiors in Winnipeg, Toronto, Saskatoon, Calgary, Victoria and Florida.
Marshall was a champion of the arts and theatre. He designed the sets and costumes for seven works of the Royal Winnipeg Ballet as well as for the Winnipeg Contemporary Dancers and Rainbow Stage. He was a board member of the Royal Winnipeg Ballet, the Royal Winnipeg Ballet School and Rainbow Stage. He chaired the decorations committee of the Winnipeg Art Gallery, designing five gala fundraisers, and sat on the advisory committee of the Manitoba Craft Guild. Marshall was inducted into the Rainbow Stage Wall of Fame in 2009. He also volunteered his design time for several non-profit institutions including Ronald MacDonald House, where he was both a member of the steering committee and the designer. He sat on the board of the Mount Carmel Clinic and the Anne Ross Daycare Centre in Winnipeg.
Painting was Marshall’s passion and he was considered a superior landscape water colour painter. Numerous solo exhibitions included Leonard Marcoe Studio Gallery, Winnipeg (six shows, 1980 – 2012) and two exhibitions at the University of Manitoba. He also participated in group exhibitions at Site Gallery (1995-2012) and at the Charles Herman Gallery in Vancouver. One of the first private art galleries in Winnipeg was opened on Osborne Street by Grant Marshall, Bruce Head and Winston Leathers in the 1960s.