So why are the currencies of Canada, Australia and New Zealand denominated in “dollars” rather than “pounds?” At what point did they break with the English monetary system, and why?
Australia’s currency was named pound until 1966, when it was replaced by the Australian Dollar (but it was not identical to the British pound - when Australia started its own currency after independence, it was at parity with the sterling, but later on it was devalued).
New Zealand switched from its pound to its dollar in 1967, and Canada (at least most of Canada) started with dollars right in the beginning, because a Spanish coin referred to as dollar by the settlers was very common, and later on of course because of the U.S. dollar.
I guess one of the most important issues that led to the switch was decimalization. The 1 pound = 20 shillings = 240 pence system might have some tradition to it, but dividing your unit of currency into 100 subunits makes calculations a lot easier. Britain didn’t introduce its New Pence, 100 of which make up a pound, until the 1970s.
Speaking as an old stamp collector…
The distinction is between decimalised currency vs the old LSD system, rather than ‘pounds’ and ‘dollars’.
Canada used dollars (a decimalised currency) from the start (ie in the 19th century), presumably because so much trade was carrying on across the border with the US. Australia and NZ switched to a decimalized currency around the early 1960s, if I recall correctly. They called the new currency the ‘dollar’ at that time, presumably to make a break with the past.
OK, a lot of ‘presumably’s’ …
I eagerly await the SD…
But why couldn’t Australia, for example, have created the “Australian Pound,” which would consist of 100 “Australian Pennies?” Bingo, instant decimalization. They didn’t adopt the U.S. dollar, so why did they adopt the U.S. nomenclature? Why call it a “dollar?”
(On preview, I see that Hemlock has speculated that they did so in order to make a clean break from the past. Possibly. But why not the “Australian Baht?” 
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