Texas was a province of Mexico when the latter seceded from Spain through a "Proclamation of Independence" by Iturbide (February 24, 1821) with a view to establishing a constitutional monarchy. At the end of about two years of Iturbide's reign, this form of government was overthrown, and he was compelled (March 19, 1823) to resign his crown. Through the efforts, principally of General Santa Anna, a Republic was established under a Constitution, modelled, in large part, on that of the United States, which went into full effect October 4, 1824. Spain did not formally recognize the independence of Mexico until 1836. The Mexican Republic was opposed to slavery, and after some of her provinces had decreed freedom to slaves its President (Guerro), September 15, 1829, decreed its total abolition, but as Texas, on account of slave- holding settlers from the United States, demurred to the decree, another one followed, April 5, 1837, by the Mexican Congress, also abolishing slavery, without exception, in Texas. Despite these decrees the American settlers carried slaves into Texas, which became part of the State of Coahuila, whose Constitution also forbade the importation of slaves. Thus was slavery extension to the southwest cut off by a power not likely ever to be in sympathy with it. It is worthy of note that neither the independent Spanish blood (notwithstanding Spain's deep guilt in the conduct of the slave trade), nor that blood as intermixed with the Indian, nor the Mexican Indians themselves, ever willingly maintained human slavery in America. Mexico's established religion under the Constitution, being Roman Catholic, did not permit its perpetuation. The Pope of Rome, in the nineteenth century and earlier, had denounced it as inhuman and contrary to the divine justice. The maintenance of slavery in Texas was regarded as of paramount importance to the South, and as slavery could not exist in Texas under Mexican authority, efforts were put forth to secure her independence, then to annex her to the United States as a State wherein slavery should exist. Even Clay, as Secretary of State, under Adams, in 1827, proposed to purchase Texas. President Jackson, in 1830, offered $5,000,000 for Texas. The Mexican Government, foreseeing the coming danger, by law prohibited American immigration into Texas, but this was unavailing, as the ever-unscrupulous hand of slavery was reaching out for more room and more territory to perpetuate itself. Americans, like their natural kinsmen the Englishmen, then regarded not the rights of others, the weak especially, when the slave power was involved. Sam Houston, of Tennessee, a capable man who had fought under Jackson in the Indian wars, inspired by his pro-slavery proclivities in 1835, went to Texas avowedly to wrest Texas from free Mexico, and, it is said, of his real intentions President Jackson was not ignorant.