Answer: Competition to develop strong economies and build large empires.
During the 19th century, England was the main imperialist power in the world and the strongest economy. However, by the beginning of the 20th century, several other nations had become wealthier and more influential in the international arena. France, Prussia (Germany), the United States and Japan were all modernizing quickly. This led to increased competition for colonies, and the resources these provided. One of the most famous examples was the Scramble for Africa. All this competition contributed to rising tensions in the years leading up to World War I.