On February 23, when the Scouts announced that the Mexican avant-garde was in sight, the unprepared Texans gathered the food they could find in the city and fell back to Alamo.  In the late afternoon, Béxar was occupied by about 1,500 Mexican troops who quickly hoisted a blood-red flag that did not mean a neighborhood.  Over the next 13 days, the Mexican army besieged the Alamo. Several small skirmishes gave the defenders the optimism they desperately needed, but had little real impact.   Bowie became ill on February 24 and left Travis alone at the helm of the Texas armed forces.  On the same day, Travis sent messengers to the people of Texas – All Americans in the World to ask for reinforcements and swear victory or death. This letter has been reproduced in the United States and much of Europe.  Texan and American volunteers began to gather in Gonzales, waiting for Fannin to arrive, and led them to strengthen the Alamo.  After days of indecision, Fannin prepared on 26 February to march his 300 soldiers to Alamo; they turned around the next day.  Fewer than 100 Texan reinforcements reached the fort.  The next morning, March 20, Urrea parodied his men and his newly arrived artillery.  When the Texans saw with Fannin the despair of their situation, they capitulated. Mexican records show that the Texans surrendered at their discretion; The Texan reports claim that Urrea promised that the Texans would be treated as prisoners of war and that they would grant transit to the United States.
 Two days later, a group of Urrea men surrounded Ward and the last of his group less than a mile from Victoria. On Ward`s strong objections, his men voted for surrender and later recalled that they had been told they would be sent back to the United States.   Cos received 650 reinforcements on 8 December, but to his dismay, most of them were brute recruits, including many inmates still in chains.  Instead of being useful, reinforcements were primarily runoff to reduce the food supply.  On 9 December, when cos and most of his men saw few other options, he recalled the Alamo mission on the outskirts of Bexar. Cos presented a counter-attack plan; The cavalry officers thought they would be surrounded by Texans and declined their orders.  Perhaps 175 soldiers from four cavalry companies left the mission and went south; Later, Mexican officers claimed that the men had misunderstood their orders and had not deserted.  The next morning, Cos gave himself.  Under the conditions of surrender, Cos and his men would leave Texas and no longer fight against the supporters of the 1824 Constitution.  With his departure, there was no longer an organized garrison of Mexican troops in Texas and many Texans believed that the war was over.  Burleson resigned as head of the army on 15 December and returned to his homeland. Many men did, too, and Johnson took command of the remaining 400 soldiers.
  Cos is perhaps best known as commander of the Mexican armed forces during the Texas Revolution of the 1830s. In September 1835, he was sent by Attorney General Antonio Lépez de Santa Anna to investigate the Texans` refusal to pay customs duties during the Anahuac riots. General Cos dispersed the legislative branch of Coahuila y Tejas, then at the meeting in Monclova, landed 300 men at Matagorda Bay, established a headquarters in San Antonio and declared his intention to end the Anglo-American resistance in Texas. He tried to stop several Texan critics of Santa Anna, but his demands were denied; A troop of Texans led by Stephen F. Austin and Edward Burleson held Mexican troops at the siege of Bexar for two months until Cos surrendered after an attack by Benjamin R. Milam in December 1835. Cos and his men were released because of their promise not to oppose the 1824 Constitution, which Santa Anna had recently repealed.