Heppner is a city in, and the county seat of, Morrow County, Oregon, United States. Take a look below for 20 obscure and interesting facts about Heppner, Oregon, United States. 1. As of 2010, the population was 1,291. 2. Heppner is part of the Pendleton-Hermiston Micropolitan Area. 3. Heppner is named after Henry Heppner, a…