Beginning in the 16th century, European powers such as Great Britain and Spain controlled and exploited far-flung territories by colonizing them. This rush to conquer and dominate land and resources uprooted and disrupted the lives of people throughout the world. Although the colonial era largely ended with national liberation movements in the 1960s, nearly four centuries of foreign control left their mark on many developing countries.

1 Better Health and Education Colonial powers introduced Western schools and healthcare, resources that often had a positive effect on the lives of the colonized people. Government schools typically focused on training for low-level civil service occupations. In many African colonies, missionaries shouldered much of the responsibility for educating the masses. Although fewer than half of the children in most colonies went to school, many of the leaders of national liberation movements who went on to lead post-colonial governments had been educated in colonial government and missionary schools. Where colonizers established medical centers, they succeeded in lowering infant mortality and promoted vaccination and disease prevention. While the colonizers did bring positive improvements and advancements, the inhabitants often lacked immunity to the pathogens the colonizers also brought from their home countries. Indigenous populations fell to plagues including smallpox, influenza and other viruses that hadn't existed within their county prior to colonization.

2 Political Strife In many territories, colonizing powers created centralized governments where none existed before. The colonizers, however, created political borders that served their own needs rather than reflecting the historical territorial divisions of the people who lived there. Suddenly, many ethnic groups that had never worked together were forced to do so. At the same time, some groups found their traditional territory divided by a political border between two colonial countries, fracturing ties between extended family and kinsmen. As a result, colonialism created large, ethnically fragmented countries prone to civil wars both during and after the colonial era.

3 Plantation Mentality Colonial powers conquered distant lands in part to exploit their natural resources, and exerted complete control of the extraction and export of cash crops and minerals -- often with little regard to helping the people native to the area. In agriculture-based colonies, a plantation economy developed, such as the coffee plantations of India and modern-day Sri Lanka. Plantation owners exerted strict control over the native people they hired to work there, often in deplorable conditions. In Southeast Asia, colonialism did have the positive effect of European investment and construction of canals and irrigation systems. African territories also saw roads and other infrastructure as a result of colonialism. However, such progress came at the expense of harsh treatment by the colonizers.