go Dutch: go on an outing where each person pays his or her own way
Go Dutch has been in use since at least the early twentieth century. Dutch in this expression is a shortened form of Dutch treat, an occasion when everyone pays his or her own expenses—in other words, no treat at all. An even older version of a skimpy Dutch social event is a Dutch feast, defined in Francis Grose's Classical Dictionary of the Vulgar Tongue as a party at which the host gets drunk before the guests. This term was obsolete by the end of the nineteenth century. Although the message—the Dutch are stingy—is similar (and similarly unfair), Dutch treat probably did not derive from Dutch feast. It's more likely that both were separately invented slurs.
Go Dutch is only one of a number of American expressions that show the Dutch in a less-than-positive light: get in Dutch (owe money or otherwise be in trouble); have Dutch courage (from drinking alcohol); do a Dutch act (desert or commit suicide); make a Dutch book (bet foolishly); give a Dutch rub (rub your knuckles against the nape of someone’s neck, a popular small boy's trick); hold a Dutch auction (where prices start high and are gradually lowered until someone bids); offer Dutch comfort ("be glad things aren't worse"); and talk double Dutch (talk gibberish).
Mutual antipathy between the British and the Dutch was well established by the time England captured New Netherland in 1664 and renamed it New York. Economic competition between the two countries was fierce and it appeared at first that the Dutch were winning. The Netherlands boasted the most powerful navy in Europe. Their trading outposts reached around the globe, including into India and China, countries where the British also hoped to gain a foothold. Dutch colonists slipped in ahead of the British to contract a trade agreement with the powerful Iroquois Confederacy. They were also strong-arming their way into England’s North Atlantic herring fishing waters. Although the British eventually triumphed in the struggle for colonies and wealth, it took them until the nineteenth century. In the meantime, they expressed their frustration through expressions like go Dutch.
Both Dutch treat and go Dutch continue to be used in modern English. Going Dutch is usually associated with dating, but sometimes announcements of organizational events like luncheons will use terms like "Dutch treat lunch."