Historically, this morpheme was used in place names to describe a location as being defensible, such as a hill, a fort, or a fortified settlement.
The earliest known references to the new name of the settlement are in letters sent by General John Forbes, dated 26 and 27 November 1758, reporting the capture of the fort.
[10][11][12] The name appeared in print at least as early as 14 December 1758, when the Pennsylvania Gazette published a letter written by a member of Forbes's army from "Pittsburgh (formerly Fort Duquesne)".
To guide its standardization efforts, the Board adopted thirteen general principles, one of which was that the final -h should be dropped from place names ending in -burgh.
While the majority of local newspapers print it without the h, certain others use the final h.[18]The Board's decisions were compulsory upon all federal government agencies, including the Post Office.
Sir: At a special meeting of the United States Geographic Board held on July 19, 1911, the previous decision with regard to the spelling of Pittsburgh without a final H was reconsidered and the form given below was adopted:
[21]With the spelling controversy largely settled, the h-less form of the city's name headed toward extinction.
Perhaps the most familiar reference to the Pittsburg spelling is on the renowned 1909 T-206 baseball card of Pittsburgh Pirates legend Honus Wagner.
[26] The city name displayed across Wagner's jersey on the card was an artistic addition that did not actually appear on the Pirates' uniforms of the time.
Additionally, the Pittsburgh Pirates city connect jerseys feature PGH written across the chest.