The term Yankee, sometimes shortened to Yank, has a few related meanings, often referring to someone either of general United States origin or more specifically, within the U.S., to people of New England origin or heritage. Its meaning has varied over time. Originally the term referred to residents of New England of colonial English descent, as used by Mark Twain in A Connecticut Yankee in King Arthur's Court (1889). As early as the 1770s the British often used the term for any American. In the 19th century Southerners used the term to refer to any Northerner who was not a recent immigrant from Europe. Thus a visitor to Richmond, Virginia, in 1818 commented, "The enterprising people are mostly strangers; Scotch, Irish, and especially New England men, or Yankees, as they are called."
Outside the United States, Yank or Yankee is a slang term, sometimes but not always derogatory, for any U.S. citizen.
Origins and history of the word
The origins of the term are uncertain, although there are many speculative suggestions. In 1758 British General James Wolfe made the earliest recorded use of the word Yankee to refer to Americans, referring to the New England soldiers under his command as Yankees: "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 the term as used by the British was often derogatory, as shown by the cartoon from 1775 ridiculing Yankee soldiers. The "Yankee and Pennamite" war was a series of clashes that occurred in 1769 over land titles in Pennsylvania, in which "Yankee" meant the Connecticut claimant. There have been many theories falsly invented including one by a British officer in 1789 who said it derives from the Cherokee word eankke, meaning coward, but there is no such word in the Cherokee language. Native American origin theories are not well received by linguists. One theory suggests the word is a borrowing from the Wendat (called Huron by the French) pronunciation of the French l'anglais (meaning the English), sounded as "Y'an-gee". During the French and Indian War the word would have been widely used among many Native Americans in the British colonies to refer to white settlers in upstate New York, throughout New England, and other areas west of the Hudson Valley. Later arrivals to the region then adopted the term with the pronunciation evolving to "Yankee". The Merriam-Webster new book of word histories (1991) p 516; Mathews (1951) p. 1896</ref>
Writing in 1819, the Rev. John Heckewelder stated his belief that the name grew out of the attempts by American Indians to pronounce the word English. The great American novelist James Fenimore Cooper supported this view in his 1841 book Deerslayer.
New Netherland is to the northwest, New England is to the northeast
Most linguists look to Dutch sources, noting there was a great deal of interaction between the Dutch in New Netherland (New York) and the Yankees of New England. The Dutch first names "Jan" and "Kees." "Jan" and "Kees" were and still are common. In many instances both names (Jan-Kees) are used as a single first name. The word "Yankee" is a variation that would refer to English settlers moving into previously Dutch areas.
Michael Quinion and Patrick Hanks argue that the term refers to the Dutch nickname and surname Janneke (from "Jan" and the diminutive "-eke", meaning "Little John" or Johnny in Dutch), anglicized to Yankee (the "J" is pronounced "Y" in Dutch) and "used as a nickname for a Dutch-speaking American in colonial times". By extension, the term grew to include non-Dutch colonists as well.
Yankee cultural history
The term Yankee now means residents of New England, and possibly the entire northeastern region. The Yankees diffused widely across the northern United States, leaving their imprint in New York, the upper Midwest, and places as far away as Seattle, San Francisco and Honolulu. Yankees typically lived in villages (rather than separate farms), which fostered local democracy in town meetings; stimulated mutual oversight of moral behavior and emphasized civic virtue. From New England seaports like Boston, Salem, Providence and New London, the Yankees built an international trade, stretching to China by 1800. Much of the merchant profits were reinvested in the textile and machine tools industries.
In religion ...
After 1800 the Yankees (along with the Quakers) spearheaded most reform movements, including abolition, temperance, women's rights and women's education. Emma Willard and Mary Lyon pioneered in the higher education of women, while Yankees comprised most of the reformers who went South during Reconstruction in the 1860s to educate the Freedmen.
Politically, the Yankees, who dominated New England, much of upstate New York, and much of the upper Midwest, were the strongest supporters of the new Republican party in the 1860s. This was especially true for the Congregationalists and Presbyterians among them and (after 1860), the Methodists. A study of 65 predominantly Yankee counties showed they voted only 40% for the Whigs in 1848 and 1852, but became 61–65% Republican in presidential elections of 1856 through 1864.