Which fruit is the principal ingredient of Slivovitz brandy?

Slivovitz, is a fruit spirit (or fruit brandy) made from damson plums, often referred to as plum spirit (or plum brandy).

Slivovitz is produced in Central and Eastern Europe, both commercially and privately. Primary producers include Bosnia-Herzegovina, Bulgaria, Croatia, the Czech Republic, Hungary, Poland, Romania, Serbia, Slovakia and Slovenia. In the Balkans, slivovitz is considered a kind of rakia. In Central Europe it is considered a kind of 'pálinka', and similar to Romanian 'țuică', corresponding to the distilled spirits category.

Only Damson plums may be used as the base fruit for distillation. During the production process, the plums and their ground kernels are crushed and pressed; yeast, starch, and sugar may be added to the juice. The mixture is then allowed to ferment. There may be one or more distillation stages, depending on the desired final product or region of production, and aging is common to enhance the distillate's finer flavours.