Aggressive German nationalism and territorial expansion was a key factor leading to both World Wars. Prior to World War I, Germany had established a colonial empire in hopes of rivaling Britain and France. In the 1930s, the Nazis came to power and sought to create a Greater Germanic Reich, emphasizing ethnic German identity and German greatness to the exclusion of all others, eventually leading to the extermination of Jews, Poles, Romani, and other people deemed Untermenschen (subhumans) in the Holocaust during World War II.