[2][better source needed] Kostić wrote around 150 lyrics, 20 epic poems, three dramas, one monograph, several essays, short stories, and a number of articles.

[3] Kostić promoted the study of English literature and together with Jovan Andrejević-Joles was one of the first to begin the systematic translation of the works of William Shakespeare into the Serbian language.

He was one of the leaders of Ujedinjena omladina srpska (United Serb Youth)[8] and was elected a Serbian representative to the Hungarian parliament, thanks to his mentor Svetozar Miletić.

[8] After Svetozar Miletić and Jovan Jovanović Zmaj, Laza Kostić was the most active leader in Novi Sad; his politics were distinct from those of his associates but he was convinced his mission to save Serbia through art had been baulked by obscurantist courtiers.

As the chief defender of the United Serbian Youth movement, Kostić was especially active in securing the repeal of some laws imposed on his and other nationalities in the Austro-Hungarian Empire.

When Mihailo Obrenović III, Prince of Serbia, was assassinated, the Austro-Hungarian authorities sought to falsely implicate Laza, his mentor Miletić, and other Serbian intellectuals in a murder plot.

In 1868, the new Prince of Serbia was the fourteen-year-old Milan IV Obrenović, who had fallen in love with Laza's most recent work Maksim Crnojević, which had been released that year.

Through Milan's influence, Kostić obtained the position of editor of Srpsku nezavisnost (Serbian Independence), an influential political and literary magazine.

Milan chose him to be Jovan Ristić's principal assistant at the 1878 Congress of Berlin and in 1880 Kostić was sent to Saint Petersburg as a member of the Serbian delegation.

Soon after, he took up residence in Cetinje and became editor-in-chief of the official paper of the Kingdom of Montenegro Glas Crnogoraca (The Montenegrin Voice),[11] where he met intellectuals Simo Matavulj, Pavel Rovinsky, and Valtazar Bogišić.

Kostić attempted unsuccessfully in numerous, incomplete theoretical essays to combine the elements of the native folk song with those of European Romanticism.

All Serbian intellectuals of the period believed the existence of their country was bound to the fate of their native tongue, then spoken widely throughout the two foreign empires.

[4][21] Kostić's translation of the fourteenth stanza from Byron's Canto III[22] of Don Juan expresses Byron's advice to the Greek insurgents: Trust not for freedom to the Franks – They have a king who buys and sells In native swords, and native ranks The only hope of courage dwells, But Turkish force, and Latin Fraud Would break your shield, however broad.

[12] After her death, Kostić wrote Santa Maria della Salute, one of his most important works[27][28] and what is said to be one of the most beautiful love poems written in Serbian language.