Born in Paris, Pierre Lacroix should initially take over his parents small shop in Marly-le-Roi. But Lacroix ambitions were with drawing and not commerce. Therefore, at the age of 17, he became the apprentice of Louis Forton, author of 'Les Pieds Nickelés', who was a client of the shop. Forton introduced him to the S.P.E. (Société Parisienne d'Édition) and in 1930, he started making illustrations for Le Pêle-Mêle. He subsequently made some advertising illustration artwork for clients like Gestetner.