Mercantilism was an economic system where countries aimed to export more than they imported in order to accumulate wealth. Under this system, colonies provided raw materials to their "mother country" since importing goods was discouraged. Great Britain passed laws like the Navigation Acts to enforce mercantilism and benefit themselves. However, they needed more labor from colonies to produce goods like wood and cotton. This led to the growth of the transatlantic slave trade, as slaves provided a source of free labor that could meet the increasing demands of mercantilism.