The question is complicated by problems of terminology. Comical graffiti exists from classical antiquity. Caricatures--portraits of individuals or types that exaggerate facial features while remaining recognizable--emerge in the Renaissance; Leonardo da Vinci was a practitioner. From the 16th century they became part of artistic training in the European art academies. They remained largely private in their intent, circulating among artists and art collectors, until the 1770s, when caricatures of public figures began to emerge as prints for public consumption in Britain--this is the origin of the political cartoon.

If by comics you mean comic books, that is, comics art in the form of sequential panels of individual scenes, these become popular in the USA in the 1930s as comic strips printed in newspapers, with the earliest examples dating to the 1890s.

Amelia Faye Rauser, Caricature Unmasked: Irony, Authenticity, and Individualism in Eighteenth-Century English Prints, 2008

Will Eisner, Comics and Sequential Art, 1985