He studied law at the universities of Heidelberg, Göttingen, Berlin, and Marburg, but soon abandoned jurisprudence for literature.

Between 1855 and 1862 he traveled, visiting Great Britain, Belgium, the Netherlands, Denmark, Italy, and Switzerland.

Rodenberg wrote the libretto to Anton Rubinstein's operas Feramors and Der Thurm zu Babel.

From 1867 to 1874 he was coeditor with Ernst Dohm of the Salon für Literatur, Kunst und Gesellschaft.

In 1874 he founded the Deutsche Rundschau, a high-quality monthly periodical for literature, culture, and politics, which he continued to edit until his death.