Not so nebulous after all.

Ok … so, just to help out on the whole Thanksgiving issue, check out this link to a York University paper: “A Canadian Original or a U.S. Copy? Forget the Pilgrims. Canada’s Own Thanksgiving Tradition Shaped by Ontario’s Protestant Clergy, Refined by Commercial, State Interests”.
Gotta hand it to those Protestant clergymen: “They created Canadian Thanksgiving as an exclusively religious event that was white, Anglo-Saxon Protestant, pro-British and often anti-American in nationalist intent.”
As for the Civic Holiday, CleverMonkey contributed this info:
“‘August Civic Holiday’ was created/suggested by a judge in Ontario
(Judge Sheard) because he wanted another long weekend near the end of
the season to take off to his cottage.
I swear this is the truth. Met him myself. Dated the sister of his
daughter-in-law.
I’m sure there were other reasons, like this was the only summer month
in Ontario without a long weekend, so it was deemed reasonable to add
another one.”
(sigh), I suppose I should also add in the Boxing Day info too, just so we’re complete on this….
Boxing Day is celebrated on December 26th. It is a statutory holiday in the federal jurisdiction and in Ontario. If it falls on a Saturday or a Sunday, the working day immediately preceding or following Boxing Day is considered a legal holiday.”