Black Horse is an unincorporated community in West Sadsbury Township, Chester County, in the U.S. state of Pennsylvania. A 1893 history of Chester County describes Black Horse as a "neat little town" having a population over one hundred, with "good school facilities", "a general store and other business concerns." It reports that that a post office was established there in 1816, first as "Black Horse Tavern", and renamed "Black Horse" in 1818. The post office was closed in 1853 and re-established in 1856. Noted People * Al Rex (born, Albert Floyd Piccirilli) (July 13th., 1928).