Colombia has been inhabited for at least 10,000 years. At the time of its exploration by the Spanish, the dominant Indian tribe was the Chibcha, a culturally advanced and warlike people.

A Spanish expedition led by Rodrigo de Bastidas reached the Caribbean coast of Colombia about 1500 In 1509 Aionso de Ojeda founded a colony on the eastern coast of the Gulf of Darien, but the settlers were soon driven off by the Chibchas. The first permanent Spanish settlement was Santa Marta, founded on the Caribbean coast by Bastidas in 1525. Cartagena, which became an important port, was settled in 1533.

In 1536 Gonzalo Jiménez de Quesada set out from Santa Marta to explore the interior. He conquered the Chibchas on the plateau of Bogotá and named the territory the New Kingdom of Granada. Santa Fé de Bogotá, which he founded in 1538, became the administrative center for the region. In 1564 New Granada was made a presidency, a political unit in the Spanish colonial system immediately below a viceroyalty. It was then ruled from Lima, Peru, until 1717, when it became a viceroyalty with Bogotá as the capital.

New Granada was a chief source of emeralds and tobacco for Spain. Indians and Africans were enslaved to work in the mines and on the haciendas (plantations). Creoles (colonial-born Spaniards) led occasional revolts against Spanish rule. They wanted reform because of high taxes and restrictions on their political and commercial activities.

In 1810 the viceroy of New Granada was deposed, and independence was declared in Bogotá. This act was the beginning of a nine-year revolution against Spain. In 1819 General Simón Bolívar of Venezuela and the Colombian General Francisco de Paula Santander led revolutionary armies over the Andes from Venezuela. The Spanish Royalists were decisively defeated at the Battle of Boyacá, and the revolutionaries formed the Republic of Colombia with Bolívar as president.

In 1821 the country was renamed Greater Colombia, and Bogotá was made the capital. Panama and Quito (now Ecuador) joined soon after. The republic collapsed in 1830 when Venezuela and Ecuador separated from it. It was reorganized in 1831 as the Republic of New Granada, and included the territories of Colombia and Panama. In 1832 Santander became president of the republic.

In 1858 the country was reorganized as the Granadan Confederation, an association of largely autonomous states. The name was changed in 1863 to United States of Colombia. Conflict between those who wanted regional autonomy in government and those who favored a strong central state was won by the centralists. In 1886 a centralist constitution was adopted, creating the Republic of Colombia.

In 1903 Colombia refused to authorize the United States to build a canal across the Isthmus of Panama. With encouragement from the United States, Panama seceded from Colombia. Panama's independence was not formally reorganized by Colombia until 1921. In the 1920's serious social unrest and growing pressure from peasants and workers led to a program of gradual social reform.

In 1932 Peru seized a portion of Colombia's territory. The League of Nations settled the dispute, returning the land to Colombia. Colombia, which had been active in the Pan American movement since its beginning in 1889, was host of the Pan American Conference of 1948, which established the Organization of American States.

Meanwhile, public discontent and political instability had become critical. Riots erupted in Bogotá following the assassination of a Liberal party leader in 1948. Disorder spread quickly as each political party tried to gain control of the countryside. Police repression was increased as civil war raged in the provinces. A military coup in 1953 brought General Gustavo Rojas Pinilla to power. The following year he was elected president by a constitutional assembly.

Rojas was ousted by a military junta in 1957. In the same year, the Liberal and Conservative parties formed a pact for cooperation in restoring civil government.

Although unrest and left-wing guerrilla warfare continued during the 1960's, the new government brought some measure of political stability and economic growth. Public support for the alliance decreased. New unrest followed the election of 1970 and threatened the survival of the government. The bipartisan pact ended in 1974.

Illicit drug traffic became a growing problem in the 1980's as Colombia became the world's largest manufacturer of cocaine. In 1994 it was revealed that the president, Ernesto Samper, had solicited campaign contributions from drug dealers. Andres Pastrana, who first brought Samper's corruption to light, was elected president in 1998. Although he immediately entered into peace negotiations with the rebels, fighting continued.