Illegal immigration in Mexico has occurred at various times throughout history, especially in the 1830s and since the 1970s. Although the number of deportations is declining with 61,034 registered cases in 2011, the Mexican government documented over 200,000 illegal border crossings in 2004 and 2005. The largest source of illegal immigrants in Mexico are the impoverished Central American countries of Guatemala, Haiti, Honduras, and El Salvador and African countries like Democratic Republic of Congo, Cameroon, Guinea, Ghana and Nigeria. The largest single group of immigrants in Mexico is from the United States, at 1.5 million, many of whom overstay their visas. Americans are the largest group of immigrants in Mexico. They number 1.5 million, many of them being without legal status since they overstayed their visas.
Texas in 19th century
In the 1820s, people from the Northern and the Eastern United States entered Mexico illegally. Mexico had legal immigration by empresario contacts to create a buffer between Mexico and the growing United States. At first, Mexico tried to convince Mexicans to move into Texas. However, Texas was dominated by the warlike Comanche Native Americans. Mexican families did not want to move to Texas and risk their families' lives. Mexico then offered cheap land to Anglos from the United States. The legal immigrants had to agree to live under the Mexican Constitution of 1824. Mexican Texas was bordered by the US frontier areas of Louisiana and Arkansas and had the most settlement by American illegal immigrants. When Mexico realized that illegal immigration was out of control, it attempted to shut it down. Mexican Texas had a population of 3,000 illegal immigrants by 1823, mostly from the Southern United States or Appalachia. By 1825, Mexico and the Coahuila y Tejas territory legalized immigration if the settlers converted to Roman Catholicism and did not own slaves. However, the settlers broke their promises, and their population expanded to 7,000 and did not assimilate to Mexican culture.
Immigration from the United States was banned in 1830 under the First Mexican Republic in an attempt to stop large numbers of white Americans from setting up cotton plantations using slave labor, which had recently been banned in Mexico. A cotton price spike and the economic success of plantations in Mississippi, which also used slaves, created strong economic incentives for illegal immigration.
By 1835, American immigration increased to 1,000 per month. Mexican President Santa Anna got rid of the Mexican Constitution of 1824. His strict dictatorship led to tensions and eventually the outbreak of the Texas Revolution. The Republic of Texas declared its independence from Mexico in 1836.
Several areas in northern Mexico fought the central government and declared independence. With a substantial number of white American settlers, the Republic of Texas quickly sought and achieved in 1845 its annexation to the United States.
Migration Law of 2011
Prior to May 2011, Mexico's immigration policy was regulated by the highly-strict General Law of Population of 1970, which had been portrayed in a hypocritical light in comparison to immigration policies by the US states, such as Arizona or Alabama. However, on May 24, 2011, Mexican President Felipe Calderón signed the new and much more liberal Migration Law. One chamber of the Mexican Congress had unanimously approved the migration bill on February 24 and the other on April 29. Some of the most significant principles of the new law included new rights for migrants. It guarantees that foreigners and Mexican nationals will receive equal treatment under Mexican law and decriminalizes undocumented immigration by reducing it to an administrative infraction, punishable with a fine of up to 100 days of the minimum wage.