Canada’s unofficial national colours will be on full display Monday as Canadians don patriotic T-shirts, wave hand-held flags and hang bunting to celebrate their country. But while the red-and-white flag for the most part unites Canadians, the colours’ meaning is open to interpretation. Xavier Gélinas, a curator at the Canadian Museum of History, said there is no authoritative source that explains why the country drapes itself in red and white. “It has never been stated clearly, explicitly anywhere, that red and white are Canada’s official colours,” he said in a recent interview. There are several schools of thought about the origins of the country’s colours, he said. Some believe they were gifted to Canada by King George V in 1921. For about a century, Gélinas said, some believed the red…