Nanjing dialect
"Peking" is a romanization created by 17th- and 18th-century French missionaries. In "De Christiana expeditione apud Sinas" (1615), Matteo Ricci calls the city "Pechinum". (The English translation gives "Pequin".) "Peking" appears in "A Description of the Empire of China" (1735) by Jean-Baptiste Du Halde. These early spellings may represent pronunciation in the Nanjing dialect, which was used as a lingua franca at this time, or the various other southern Chinese languages (e.g., Cantonese, Hokkien and Hakka) used by the traders of the port cities visited by early European traders.