<span>The 19th century was a period of great change and rapid industrialization. The iron and steel industry spawned new construction materials, the railroads connected the country and the discovery of oil provided a new source of fuel. The discovery of the Spindletop geyser in 1901 drove huge growth in the oil industry. Within a year, more than 1,500 oil companies had been chartered, and oil became the dominant fuel of the 20th century and an integral part of the American economy.</span>
The correct answer to this open question is the following.
You did not specify what war you are talking about. Trying to help you we are going to assume that you are talking about World War I.
In addition to fighting in the army, European colonies contributed to the war effort in that these colonies sent supplies and food to the war front in Europe.
European superpowers had colonies in Africa, India, and Asia, places where there were plenty of natural resources and raw materials that were much needed by European countries during World War I. Great Britain and France were the European countries that used most soldiers from their colonies after many white troops were killed on the battlefield.
Answer:
The trade routes of Ancient Africa played an important role in the economy of many African Empires. Goods from Western and Central Africa were traded across trade routes to faraway places like Europe, the Middle East, and India.
