Following is brief account of some of the Mexico City facts. There are hundreds of Mexico fast facts. Mexico is the world's most populous Spanish-speaking country. Mexico has a significantly high foreign debt . Its land is rich, but much of it is difficult to cultivate. Despite the prosperity of its oil industry, Mexico's economic troubles are severe. Many Mexicans cross the Mexican-American border illegally in hopes of finding work in the United States . Other facts about Mexico City include Mexico's proximity to the United States has led to serious territorial disputes; the immediate cause of the Mexican War of the 1840s was the annexation of Texas by the United States . Mexico became independent from Spain in 1821. Before the arrival of the Spanish in the early sixteenth century, great Native American civilizations, such as the Mayas and the Aztecs , thrived. In 1994, Mexico joined the North American Free Trade Agreement (NAFTA).
