Muir wrote several songs about Canada during his career, including Canada Forever and Young Canada Was Here, but his most enduring composition was The Maple Leaf Forever  written in 1867, the year of Confederation.
While Muir wrote numerous songs about Canada during his career, including "Canada Forever" and "Young Canada Was Here," his most famous piece is "The Maple Leaf Forever," which he penned in 1867, the same year Canada became a unified nation.