The British wanted to monopolize slave trade in the late 17th century because it was a prosperous business venture. Colonists in America and the West Indies were dependent on the strong, imported labor force that came primarily from Africa, and England had the ships, money and power to provide the labor. By taking over the slave trade, the British also held the upper hand in their political and economic involvement in the American colonies, leaving little room for competing European countries to take advantage of the newly developing colonies and their dependence on slave trading.

Prosperous Sugar Plantations

The British desired control of the slave trade so they could benefit from the Caribbean sugar plantations. Until 1640, the English had been opposed to the idea of slavery, but the economic benefits associated with sugar exportation were undeniable. The growth and harvest of sugarcane required a large labor force and the British quickly realized that indentured servants from Britain and a few African laborers weren't enough to meet production demands. A triangular British-organized slave trade from England to Africa and then to America and the West Indies was necessary.

Economic Prosperity

In 1660, England created a company called the Company of Royal Adventurers Trading to Africa. The government-supported charter stated that other English merchants weren't allowed to compete in the slave trade market between England and the British colonies in the West Indies, giving the company a huge financial advantage. However, due to the war with Holland, the company collapsed in 1667. Nonetheless, England's attempt to control the slave trade didn't end there.

Monopolization

Britain wanted to ensure its dominant role in the slave trade, thus controlling imported labor costs and expenses associated with the industry. England founded a new company in 1672 -- the Royal African Company. The English government, under the rule of King Charles, once again gave monopoly rights to a single slave-trading company. By controlling slave trade, the British were able to set the price for purchasing workers and oversee the exportation of goods, including shipping costs. Between 1680 and 1686, the Royal African Company transported an average of 5,000 slaves a year and financed 249 voyages to obtain slaves. British seaports in London, Bristol and Liverpool were major ports in the slave trade.

Colonization Efforts

England needed to make sure its colonization efforts succeeded and ward off other European involvements. Without an effective labor force, the economic stability of British-controlled colonies in the West Indies and America would have likely failed. Americans weren't politically or economically equipped to manage crop production, oversee commerce, export goods or participate in international trade on their own, especially without a stable and reliable imported workforce. The British government couldn't risk Portugal or Holland assuming the lion's share of slave trade in the region or it could lose momentum in its colonization efforts.