Pittsburgh

wiktionary

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Pitt +‎  -s- +‎  burgh After William Pitt the Elder, followed by  burgh ("fortress") 

etymonline

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Pittsburgh

city in Pennsylvania, U.S., founded 1754 by the French and called Fort Duquesne in honor of Michel-Ange Duquesne (1702-1778), governor of New France; captured by the British 1758 and renamed in honor of British statesman William Pitt the Elder (1708-1778). The Scottish -burgh is unusual in the U.S. (compare Edinburgh) and may be from the Scottish officers who led its capture in the Seven Years War. The spelling varied with -burg in 19c., but when the U.S. Board on Geographic Names regularized all -burgh spellings to -burg, the Pittsburghers protested, and the -h officially was restored in 1911