Kočevski Rog massacre
1945 CE.
Shown on the map at 45.670°, 14.936°.
The Kočevski Rog massacre was a series of massacres near Kočevski Rog in late May 1945 in which thousands of members of the Nazi Germany–allied Slovene Home Guard were executed, without formal charges or trial, by special units of the Yugoslav Partisans; other victims were Croats, Serbs, and Montenegrins that had fought on the Axis side as well as much smaller numbers of Italian and German troops.
Text from the Wikipedia article Kočevski Rog massacre, licensed CC BY-SA 4.0.