In 1857, Karavelov enrolled in the Faculty of History and Philology at the University of Moscow, where he fell under the influence of Russian revolutionary democrats, was placed under police surveillance in 1859, and took part in student riots in 1861.

At his first newspaper Svoboda (Freedom) in Bucharest (1869–1873), he worked and became friends with poet and revolutionary Hristo Botev who devoted a poem to him.

Although Karavelov, the older of the two, was the recognized master, both of them were very good professional journalists, setting high standards for Bulgarian language and literature.

Following the capture and execution of Levski in 1873, though, the disheartened Karavelov gradually abandoned his revolutionary zeal, attracting Botev's severe criticism, and started publishing a new Znanie (Knowledge) journal and popular science books.

His younger brother Petko was a prominent figure in Bulgaria's political life in the late nineteenth century.