Patriation

Patriation was the political process that led to Canadian sovereignty, culminating in 1982. Until then, Canada was governed by a constitution composed of British laws that could be changed only by acts of the British parliament, with the consent of the Canadian government.

The patriation process saw the provinces granted influence in constitutional matters and resulted in the constitution being amendable by Canada only and according to the Canadian amending formula, with no role for the United Kingdom. Hence, patriation is associated with the acquisition of full sovereignty.

The word patriation was coined in Canada as a back-formation from repatriation (returning to one's country). As the Canadian constitution was originally a British law, it could not return to Canada. The term was first used in 1966 by Prime Minister Lester B. Pearson in response to a question in parliament: "We intend to do everything we can to have the constitution of Canada repatriated, or patriated."

From 1867, the Constitution of Canada was primarily contained in the British North America Act, 1867, and other British North America Acts, which were passed by the Parliament of the United Kingdom. Several Canadian prime ministers, starting with William Lyon Mackenzie King in 1927, had made attempts to domesticize the amending formula, but could not obtain agreement with the provincial governments as to how such a formula would work. Thus, even after the Statute of Westminster granted Canada and other Commonwealth nations full legislative independence in 1931, Canada requested that the British North America Act, 1867, be excluded from the laws that were now within Canada's complete control to amend; until 1949, the constitution could only be changed by a further act at Westminster. The British North America (No.2) Act, 1949, granted the Parliament of Canada limited power to amend the constitution in many areas of its own jurisdiction, without involvement of the United Kingdom. The constitution was amended in this manner five times: in 1952, 1965, 1974, and twice in 1975.

...
Wikipedia