European nations competed for power before World War 1 by:
i) Imperialism- In the late 1800 and early 1900 some European Nations gained control of new territories. The acquisition of colonies would provide raw materials for the growing industries, and provide a market to sell their manufactured products.
ii) When their industries were stable, they would strengthen their armies by building up the nations military forces as a way to increase the nation's prestige and power in the world by the expansion of their armies and navies.
iii) Formation of Alliances- European Nations formed alliances with other countries to protect their interest in written treaties to come to each others aid if one of the nations were attacked.
iv) Nationalism- This is the feeling of where one's country must win a more significant place in the world.