From the OED2:

colloq.
Also Kanuck, etc. [App. f. the first syllable of Canada.]
1. A Canadian; spec. a French Canadian.
2. A Canadian horse or pony.
3. The French-Canadian patois. B. adj. Of or pertaining to Canada or its inhabitants.
In U.S. usage, gen. derogatory.
1835 H. C. Todd Notes upon Canada 92 Jonathan distinguishes a Dutch or French Canadian, by the term Kanuk.


Same source:

Yankee
Also Yankey, Yanky, pl. Yankies. [Source unascertained.
The two earliest statements as to its origin were published in 1789: Thomas Anburey, a British officer who served under Burgoyne in the War of Independence, in his Travels II. 50 derives Yankee from Cherokee eankke slave, coward, which he says was applied to the inhabitants of New England by the Virginians for not assisiting them in a war with the Cherokees; William Gordon in Hist. Amer. War states that it was a favourite word with farmer Jonathan Hastings of Cambridge, Mass., c 1713, who used it in the sense of ‘excellent’. Appearing next in order of date (1822) is the statement which has been most widely accepted, viz. that the word has been evolved from North American Indian corruptions of the word English through Yengees to Yankees (Heckewelder, Indian Nations iii. ed. 1876, p. 77); cf. Yengees.
Perhaps the most plausible conjecture is that it comes from Du. Janke, dim. of Jan John, applied as a derisive nickname by either Dutch or English in the New England states (J. N. A. Thierry, 1838, in Life of Ticknor, 1876, II. vii. 124).

Hence "Yankee v. (rare—1), trans. to deal cunningly with like a Yankee, to cheat […]
1837 Fraser's Mag. XVI. 683 [They] are considered capable of ‘*Yankeeing’ the more simple-minded Canadians.



Not that I’d want to stir up old wars or anything but