At the time of his arrest, Austin had been a strong supporter of Texas as a separate state within Mexico. He had sworn a loyalty oath to Mexico and meant to keep it. Eighteen months in prison, however, helped to change his mind.
With their leader under Santa Anna's control, Texians (who feared for Austin's life) were relatively quiet (between 1833 and 1835). But when Austin walked out of his prison cell for the last time, Santa Anna was Dictator of all Mexico. Two hundred days which changed Texas were about to begin.
From the president's perspective, Texians were troublemakers who needed to be controlled. He banned Texas slavery (in 1835) and feared the expansionist tendencies of Mexico's neighbor to the north - the country from which Anglo-Americans had immigrated. Santa Anna believed the colonists would revolt absent strong, centralized government.
Texians (who numbered 20,000 by 1834) feared expulsion from their land. They, together with the Tejanos (who had long desired local rule), were convinced a dictator was deliberately disrupting their way of life and meant to end his interference one way or another.
Some of the key events, leading to the birth of Texas as an independent country, occurred between October of 1835 and March of 1836:
If Texas will now act promptly; she will soon be redeemed from that worse than Egyptian bondage which now cramps her resources and retards her prosperity.
As Santa Anna's army positioned itself around the old mission, those inside were worried. Would they get reinforcements? Would there be enough supplies to hold out during a siege?
Today the San Antonio de Valero Mission is known by two simple words: The Alamo.