Colombia is marked by three parallel mountain ranges of the Andes mountain chain. Vast stretches of lowlands to the east of the mountains are thinly populated and only partly explored. About 73 percent of the population is urban, and most are Roman Catholic. The racial makeup of the country includes mestizo (mixed Spanish and Native American), European, mulatto (mixed black and white), black, and Native American ancestry. Spanish is the official language.
Early in the nineteenth century, the country won its independence from Spain, and the great revolutionary Simón Bolívar became first president of the new republic. A new constitution was adopted in 1886, and the present basic structure of the country was established. The first half of the twentieth century was one of severe political turmoil between liberal and conservative political factions. The National Front brought a measure of stability to the country in the 1960s, but since then, Colombia has been plagued by political corruption, drug wars, guerrilla activity, and terrorist violence.