How did 'patriate' develop to mean 'transfer ... from a mother country to its former dependency'?

Question

What's an intuitive derivation behind ODO's definition that helps to internalise its meaning:

to patriate = Transfer control over (a constitution) from a mother country to its former dependency:

Etymonline: 1966, in Canadian English (perhaps coined by Lester B. Pearson) in reference to constitutional laws, probably a back-formation from repatriate.

Wikipedia: The word "patriation" was invented 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.

So I know that this is a Canadian term, but what's the relationship between it could not "return to" Canada and the elimination of the prefix 're'? How's this word a 'back-formation'?

Answer 1

Patria is derived from Latin (fatherland) and, in English, means

One’s native country or homeland: they remained faithful to their patria, Spain [Oxford Dictionaries Online]

When a colonial power transfers power to a colony, the old father/motherland is no longer the homeland. The former colony now becomes its own homeland. At that moment, a new patria has been created.

While the current usage of patriate may be based on a back-formation from re-patriate, the logic holds.

The phrase in the Wikipedia article merely points out that, as Canada became independent, it was not going back, but forward. Repatriation of Canada or its constitution would be re-attaching it to the former homeland, England.

Answer 2

"Repatriate" means "to bring back to its original land/country," the prefix "re-" here giving the coming back home part of the meeting.

Historically, as a British colony and later as a dominion of the British Empire, Canada did not have a home-grown constitution. It was originally a British document, so could not logically "return home" to Canada in the sense of coming back to the land where it originated, hence the perceived need to have a word indicating a "one-way trip."

If the Canadians ever, for some reason, returned responsibility for the Constitution to GB, it would be repatriated.