A mari usque ad mare

The phrase comes from the Latin Vulgate translation of Psalm 72:8 in the Bible: "Et dominabitur a mari usque ad mare, et a flumine usque ad terminos terrae"(King James Bible: "He shall have dominion also from sea to sea, and from the river unto the ends of the earth").

His great-grandson Michael Ignatieff suggests that Grant used the phrase in a nation-building effort during the construction of the Canadian Pacific Railway.

[1] This phrase was suggested for a national motto by Joseph Pope, then-Under Secretary of State, when the Canadian coat of arms was redesigned in 1921.

[1] The draft design was approved by Order in Council on April 21, 1921, and by the Royal Proclamation of King George V on November 21, 1921.

[6] As part of the Canadian coat of arms, the motto is used as a mark of authority by various government agencies and representatives.

The motto within the Canadian coat of arms
The Arms of Canada as designed in 1921 with the national motto and original green maple leaves.