Background: Following three centuries under the rule of Portugal, Brazil became an independent nation in 1822. By far the largest and most populous country in South America, Brazil has overcome more than half a century of military intervention in the governance of the country to pursue industrial and agricultural growth and development of the interior. Exploiting vast natural resources and a large labor pool, Brazil became Latin America's leading economic power by the 1970s. Highly unequal income distribution remains a pressing problem.