How did european imperialism contribute to the start of world war i?
(can you wright a short answer version? )

A short answer is that becasuse of the imperialism of European nations there was a growing dissatisfaction in those nations who did not have any colonies. Due to not having colonies they argued for a redistribution in colonies so that it would be more equally and fairly shared. Because this didn't happened (among with A LOT of other reasons), World War I ensued. 

To have a bunch of countries to team up, and communicate not let the communist break them apart and take over the world