Poland China
The oldest pig breed in the USA

Apart from bizarre names, pig breeds also have their histories. The origins of the pigs known as Poland China or the Warren County Hogs date back to 1816 when breeders in Ohio in the American Midwest started to experiment with corssing Chinese type pigs with several European breeds. The name might suggest that some of the breed founders came from Poland but in fact, it is a misunderstanding stemming from one person who used the word Poland to designate the progeny of a particular animal bought from a Polish-born farmer.

Poland China boars raised by J.C. Herlong: Micanopy, Florida. July 15, 1917.
Breeders typically selected pigs for desired characteristics such as weight gain or fecundity and differentiated between good "feeders" and "breeders." Poland China hogs were bred for lard. With the advancements in transport infrastructure in the mid-19th century, the demand for pigs to be good "travelers" declined. In other words, they did not need to be driven for miles to distant markets. The result was large, round, short-legged pigs with quiet temperament.
To explore the history of the oldest pig breed in North America, read the book History of the Poland China breed of swine published in 1921 by the Poland China History Association.