Complex sentence: After his graduation, he started his journalism career in 1842 at the "Courrier du Haut-Rhin", before moving to Paris where he was employed by Émile de Girardin in the editorial department of "La Presse" in 1844.
Split into simpler sentences: After his graduation, he started his journalism career in 1842 at the "Courrier du Haut-Rhin". He then moved to Paris, where he was employed by Émile de Girardin in the editorial department of "La Presse" in 1844.