The Online Etymology Dictionary gives its origin as around 1683, attributing it to English colonists insultingly referring to Dutch colonists. English privateer William Dampier relates his dealings in 1681 with Dutch privateer Captain Yanky or Yanke. Linguist Jan de Vries notes that there was mention of a pirate named Dutch Yanky in the 17th century. The Life and Adventures of Sir Launcelot Greaves (1760) contains the passage, "Haul forward thy chair again, take thy berth, and proceed with thy story in a direct course, without yawing like a Dutch yanky." According to this theory, Dutch settlers of New Amsterdam started using the term against the English colonists of neighboring Connecticut.
British General James Wolfe made the earliest recorded use of the word "Yankee" in 1758 when he referred to the New England soldiers under his command. "I can afford you two companies of Yankees, and the more, because they are better for ranging and scouting than either work or vigilance". Later British use of the word was in a derogatory manner, as seen in a cartoon published in 1775 ridiculing "Yankee" soldiers. New Englanders themselves employed the word in a neutral sense; the "Pennamite–Yankee War", for example, was a series of clashes in 1769 over land titles in Pennsylvania between settlers from Connecticut Colony and "Pennamite" settlers from Pennsylvania.
Many etymologies have been suggested for the word Yankee, but modern linguists generally reject theories that suggest it originated in any Indian languages. This includes a theory put forth by a British officer in 1789, who said that it was derived from the Cherokee word eankke meaning "coward"—despite the fact that no such word existed in the Cherokee language. Another theory surmised that the word was borrowed from the Wyandot pronunciation of the French l'anglais, meaning "the Englishman" or "the English language", which was sounded as Y'an-gee.
The meaning of Yankee has varied over time. In the 18th century, it referred to residents of New England descended from the original English settlers of the region. Mark Twain used the word in this sense the following century in his 1889 novel A Connecticut Yankee in King Arthur's Court. As early as the 1770s, British people applied the term to any person from the United States. In the 19th century, Americans in the southern United States employed the word in reference to Americans from the northern United States, though not to recent immigrants from Europe. Thus, a visitor to Richmond, Virginia, commented in 1818, "The enterprising people are mostly strangers; Scots, Irish, and especially New England men, or Yankees, as they are called".
An early use of the term outside the United States was in the creation of Sam Slick the "Yankee Clockmaker" in a newspaper column in Halifax, Nova Scotia, in 1835. The character was a plain-speaking American who becomes an example for Nova Scotians to follow in his industry and practicality; his uncouth manners and vanity were qualities that his creator detested. The character was developed by Thomas Chandler Haliburton, and it grew between 1836 and 1844 in a series of publications.
Yankees dominated New England, much of upstate New York, and much of the upper Midwest, and were the strongest supporters of the new Republican party in the 1860s. This was especially true for the Congregationalists, Presbyterians, and Methodists among them. A study of 65 predominantly Yankee counties showed that they voted only 40 percent for the Whigs in 1848 and 1852, but became 61–65 percent Republican in presidential elections of 1856 through 1864.
Major League Baseball's New York Yankees acquired the name from journalists after the team moved from Baltimore in 1903, though they were officially known as the Highlanders until 1913. The regional Yankees–Red Sox rivalry can make the utterance of the term "Yankee" unwelcome to some fans in New England, especially to the most dedicated Red Sox fans living in the northeastern United States.
The one anomaly of this era was the election of Yankee Republican Leverett Saltonstall as governor in 1938, and even then Saltonstall jokingly attributed his high vote totals in Irish districts to his 'South Boston face'.