Today is the anniversary of a significant event in Texas history: the Battle of San Jacinto. On April 21, 1836, near modern-day Houston, Texas, a battle lasting a mere 18 minutes marked the successful end of Texas’ war for independence. Before that, Texas had been part of Mexico.

Mexico had been a colony of Spain but gained its independence in the 1820s. Because Texas’ population was sparse, Mexico was happy to welcome foreigners to settle the territory.

About 25,000 immigrants, most of them American, settled along the Brazos River in the decade after Mexico declared independence from Spain.

Though the “American” Texans were legally Mexican citizens, they continued to speak English and traded closer with the United States than Mexico. These Anglo-American residents of Mexican Texas were called Texians.

In 1835, Mexico’s president, General Antonio Lopez de Santa Anna, overthrew the Mexican constitution and declared himself a dictator. Worried that the Texians would try to secede from Mexico now that he had seized power, Santa Anna ordered the Mexican military to disarm them.

The first indication that disarming the Texians would prove difficult came on October 2, 1835, when the Mexican army tried to take a cannon from a village in Gonzales. Mexican troops told the Texians to surrender, and they responded defiantly with, “Come and take it.”

The Texians’ resistance escalated and ended with the Mexicans retreating. After that point, battles for Texas’ independence from Mexico continued.

Leading up to San Jacinto, Texas’ volunteer soldiers suffered defeat at the hands of the troops led by General Santa Anna. They retreated to the Alamo, an 18th-century Franciscan Mission located in modern-day San Antonio.

The Alamo is the site of one of the most memorable battles of the war. The group of men, outnumbered by an estimated nine to one, held off the Mexican army for 13 days before they were finally overpowered.

Santa Anna left no survivors. All of the 189 Texians that fought were killed, and Santa Anna had their bodies burned.

During the Battle of the Alamo, delegates from Texas held the Convention of 1836, where they declared Texas’ independence and formed the Republic of Texas.

Upon learning of the events at the Alamo, Sam Houston spent a month in preparation before launching the next attack. The Texian army scouted the Mexican military and discovered they were vulnerable during their “siesta,” an afternoon nap taken during the hottest parts of the day.

On April 21, 1836, Houston’s army defeated Santa Anna’s at the Battle of San Jacinto, near present-day Houston. Roughly 800 Texians defeated almost twice as many Mexicans in the 18-minute battle. Houston’s forces shouted, “Remember the Alamo.”

Santa Anna was taken prisoner, along with hundreds of his soldiers. In mid-May of the same year, the Mexican general signed a peace treaty for his freedom that officially recognized Texas’ independence.

Houston was elected the first president of the Republic of Texas. He would later serve as senator and then governor of the State of Texas after it joined the United States in 1845.

Texans have a great deal of pride in the battle lost at the Alamo and the victory won at San Jacinto. To celebrate the final battle that won Texas its independence, April 21 was designated “San Jacinto Day.”

Each year, a festival takes place on the battle site in observance of the victory. As part of the celebration, the Sabine Volunteers, named for one of the militia groups that fought at San Jacinto, reenact the battle’s events.