Until 1821, Mexico and Texas had been ruled by Spain. In 1821, Mexico fought against Spain and gained its independence. As a result, Texas also became a part of Mexico. For a time, Mexican government followed federalist policies. This meant that Texans made most of their local decisions on their own while the central government didn’t interfere much.
This changed when General Santa Anna became the head of Mexican government. He wanted to increase the power of his government and control areas such as Texas more strongly. The Texans didn’t like it and in 1835, they launched the Texas Revolution.
By 1835, relationships between Texans and the Mexican government weren’t exactly friendly. In October, 1835, a group of Mexican soldiers was sent to take back a cannon from the town of Gonzales. The Mexican government had previously given the cannon to the town for protection but now the government feared that white settlers in the town may use it to fight the Mexican army.
On the other hand, settlers in the town thought that the army wanted back the cannon back so that it could later defeat them more easily. They refused to give the cannon back and at the same time attacked the Mexican soldiers who retreated. This event marked the beginning of the Texas Revolution
Soon after the incident at the town of Gonzales, a larger group of Mexican soldiers reached Bexar in Texas. The leader of this group was General Martin Perfecto de Cos. By this time, volunteers and Texan soldiers from all over Texas had been brought together as a small army.
This army decided to attack Bexar and force the Mexican soldiers to either retreat or leave Texas. The Texan army was led by Stephen F. Austin and included famous fighters such as James Bowie. Texan army reached Bexar and laid siege to the town. The siege began on October 12, 1835 and continued until December 11, 1835.
During the siege, reinforcements continued to arrive on both sides. By December, Mexicans inside Bexar had 1200 soldiers while the Texans who had laid siege to the town had 600 men. By this time, the morale was low on both sides and men were getting tired. So Texans decided that they had to take the town now or their siege would fail.
On December 5, 1835, the Texan army finally attacked the town. They were able to reach inside the town, forcing Mexican soldiers to retreat. The Mexican army under General Cos initially retreated to the fort of Alamo just outside of Bexar. But by this time, Mexican soldiers had no interest in fighting and most of them left Cos and went back to Mexico. This forced General Cos to surrender to the Texans on December 11, 1835.
The Texans scored another important victory at the Siege of Bexar. The defeat of the Mexican garrison assured them that they could fight and defeat a proper army. However, the fighting was far from over. General Santa Anna in Mexico was furious that General Cos had surrendered. And he vowed to take back control of Texas. Later in December 1835, Santa Anna and a large Mexican army headed towards Texas. This army would eventually fight at the Battle of the Alamo and the Battle of San Jacinto, both fought in 1836.