O Canada

Today is "Canada Day", the day that celebrates when the British Parliament passed a law to unite the separate Canadian colonies into one in 1867, an act that got passed primarily because the Pommies had gotten tired of running the place.*

Which, of course, wasn't really independence.**

Canada didn't become a fully-independent nation until possibly 1931 or 1982, depending on what your definition of "independence" is. Which is probably why it took the Canadians about sixty or so years after the enactment of that law for them to get around to celebrating it.
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* Also, if the Americans invaded, the Brits wanted the option to just say "oh, well" and forget about it. Which would have been difficult for them to do if they still owned it (something the Argies found out the hard way).

** When the Brits declared war in 1914, Canada, as well as Australia and New Zealand, were dragged into the war whether they liked it or not.