After the war, he completed his degree in Slavic languages and worked as a reporter for the newspaper Vjesnik, as an editor for a publishing company called “Nopok,” and then as the assistant Chair of the department of Yugoslav literature at the Faculty of Arts in Zagreb.
"[8] “His cycle Tifusari (Typhus Victims), together with Goran Kovačić’s Jama (The Pit) and Popovič’s Oci (Eyes), is no doubt artistically the most dramatic saga of suffering, death, yearning after life in Yugoslav Partisan Poetry.
On the other hand, even in the midst of wartime ferocity, Kaštelan found within the Partisan Resistance movement a spirit of comradeship that brought a glimmer of light into the darkness of his despair and that has inspired many of his best poems” (Columbia).
"[3] “Some critics have seen in Kaštelan’s work the influence of folk poetry and surrealism, as well as that of such writers as Dragutin Tadijanović, Miroslav Krleža, Federico García Lorca, and Walt Whitman” (Columbia).
[3] Though Kaštelan is best known for his poetry, he also wrote a play (Pijesak i pjena, Sand and Foam; 1958),[3] a collection of short stories (Čudo i smrt, Wonder and Death),[12] numerous essays, articles, commentaries, and criticisms of contemporary Croatian poets.