Black Lamb and Grey Falcon by Rebecca West (1941) is the classic account of Yugoslavia before World War II, including extended sections on Croatia and Dalmatia. Dense, brilliant, and opinionated — essential reading for anyone wanting depth beyond the tourist surface.
Croatia: A Nation Forged in War by Marcus Tanner is a solid history covering Croatian identity from the medieval period through the 1990s war. Clear and unsentimental.
The Culture of Lies by Dubravka Ugrešić is a sharp collection of essays by Croatia's most provocative contemporary writer, examining nationalism, identity, and the cultural disorientation of the post-Yugoslav period. Ugrešić was effectively exiled for writing it.
Café Europa: Life After Communism by Slavenka Drakulić gives a ground-level account of the post-communist transition across Central and Eastern Europe, including Croatia. She writes with precision and bite.
Balli di Sfessania — for something different: Croatia's Dalmatian coast and islands have inspired a small shelf of sailing and travel memoirs. Tristan Jones's Saga of a Wayward Sailor includes time in the Adriatic; more recently, To the Baltic with Bob by Griff Rhys Jones touches on the Croatian coast.
Lonely Planet Croatia remains the most practical current guidebook for on-the-ground detail. The Rough Guide to Croatia is a good alternative.
For fiction, The Ministry of Pain by Dubravka Ugrešić follows Croatian exiles in Amsterdam grappling with the loss of Yugoslavia — unsettling and very good. On the Edge of Reason by Miroslav Krleža is an older but essential Croatian novel, a satirical account of a man's breakdown under the pressures of provincial bourgeois society between the wars.
The Practical Guide to Croatia's Archaeological Sites by Ante Šušnjara covers Illyrian hillforts, Greek colonies, Roman amphitheatres, and Celtic settlements across the country, pairing modern place names with their ancient equivalents and including underwater sites along the Adriatic. Useful if you want to go beyond Diocletian's Palace and explore lesser-visited ruins.