The story started in the 1820's when Mexico encouraged settlement of Texas by ambitious American planters in order to add a share of potentially huge cotton profits to Mexican tax revenues and, likely, to aid in control of indigenous people. The settlers were Southerners, familiar with cotton agriculture and the administration of the numbers of slaves necessary to accomplish cotton's brutal labour demands. The settlers brought their slaves with them, so from the beginning that there was approximately one slave for every 5 Texans. The Texans enjoyed years of freedom to develop their property and become established in Texas. Their investment produced a potentially large tax revenue source for Mexico as well. Allowing the Texans to continue to keep slaves to work the fields and pick the cotton kept the relationship going. The Texans, after all, were producing large amounts of valuable cotton on the otherwise desolate northern Mexican lands, which enabled them to pay taxes to the cash starved Mexican government. Also, it helped secure the land against Indian claims. However, events outside the control of Texans threatened this mutually prosperous relationship.
Mexico had a politically active abolitionist movement . In September of 1829 slavery was prohibited in Mexico. Because the politically connected Texans were outraged, one month later, the law was changed to allow slavery only in Texas. A few months later in early 1830, Mexico altered its policy under a new government that was less interested in catering to Texas. Mexico passed a law that prohibited further American settlement, and banned importation of additional slaves into Texas. The Mexican abolition movement, following the pattern seen around the world, had apparently pressured for more restrictions. This was a strict proviso, but for the Texans it was survivable, as they already had thousands of slaves within Mexico. The law must have created difficulties for the Texans and been a great source of irritation to them as they worked to develop their slave labour based agricultural economy. There were other grievances by this time, such as the amount of taxes the Texans were required to pay, but none struck home so much as the "bread and butter" issue of slavery. Without it, the Texans could not make a profit and ultimately would be out of business.
As the American population of Texas grew increasingly disgruntled with the various restrictions imposed by Mexico, an independence movement developed led by Stephen Austin. He presented a petition for independence to the Mexican government in 1833, and was then arrested and jailed until 1835. In 1835, there were about 20,000 Texans and 4000 slaves in Texas. In December of 1835 the newly crowned dictator General Antonio Santa Anna amended the slavery laws to ban slavery in Texas.
The settlers and their newly freed leader Austin quickly announced that they would secede from Mexico. To the great dismay of the Texans, however, in December of 1835 President Santa Ana extended the slavery ban to Texas to appease Mexican abolitionists. The Texans immediately rebelled and declared that they were seceded from Mexico, and declared the Republic of Texas. One of their first actions was to ban free blacks from the Republic. Not content with the possibility of withdrawing from Texas, the Texans enlisted the help of citizens of the United States in order to preserve slavery and the huge tracts of cotton growing land. This resulted in the famous siege and battle at the Alamo, a Catholic mission taken over by the Texans.
