In 1924, the Red Ensign was approved for use on Canadian government buildings outside Canada, and in 1945, the flag was officially approved for use by government buildings inside Canada as well, and once again flew over Parliament.
From 1865 until Canadian Confederation in 1867, the United Province of Canada could also have used a blue ensign, but there is little evidence such a flag was ever used.
In recent years, many far-right and neo-Nazi groups in Canada, particularly those affiliated with Paul Fromm, have attempted to appropriate the Canadian Red Ensign as a symbol of their movement to emphasize what they assert is their adherence to traditional Canadian values.