The Tree with No Name by Drago Jančar — Slovenia's most internationally recognised novelist, Jančar writes dark, historically layered fiction rooted in the complicated 20th-century history of Central Europe. This novel is less directly about the Istrian coast than his earlier work, but his prose gives you an understanding of the weight of history that sits under the surface of these small Adriatic towns — places that changed hands between Austria, Italy, and Yugoslavia within living memory.
Alamut by Vladimir Bartol — Technically set in medieval Persia and not in Istria at all, but this 1938 novel by a Slovenian writer was rediscovered as an international classic in the 1980s and 90s. Its themes of loyalty, manipulation, and the use of belief as a political tool resonate with the region's 20th-century history. The best introduction to Slovenian literary ambition for a reader new to the culture.
The Slovenians: Their History and Culture by various editors — For the historically curious traveller, this collection of essays provides the cultural context that helps make sense of why this small, prosperous country has such a distinct identity despite centuries of Habsburg rule and decades of Yugoslav federation. The section on Istria — the contested peninsula that was Italian until 1947 and is now split between Slovenia and Croatia — is directly relevant to understanding Portorož and its surroundings.
Mediterranean Winter: The Pleasures of History and Landscape in Tunisia, Sicily, Dalmatia, and Greece by Robert D. Kaplan — Not specifically about Slovenia, but Kaplan's chapter on the eastern Adriatic is one of the best short accounts of what makes this coastline — its Venetian legacy, its compressed history, its particular quality of light — so different from the western Mediterranean. A useful companion for anyone travelling the Adriatic arc from Venice south through Slovenia and Croatia.