Trpinja is a village and an eponymous municipality in the Vukovar-Syrmia County in eastern Croatia. The village is located on the D55 road between Osijek and Vukovar. Landscape of the Trpinja Municipality is marked by the Pannonian Basin plains and agricultural fields of corn, wheat, common sunflower and sugar beet.

Vukovar-Srijem County, Vukovar-Sirmium County or Vukovar-Syrmia County, named after the eponymous town of Vukovar and the region of Syrmia, is the easternmost Croatian county. It includes the eastern parts of the region of Slavonia and the western parts of the region of Syrmia, as well as the lower Sava river basin, Posavina and Danube river basin Podunavlje. Due to the overlapping definitions of geographic regions, division on Slavonia and Syrmia approximately divides the county vertically into north-west and south-east half, while division on Posavina and Podunavlje divides it horizontally on north-east and south-west half.