Seguin ( /səɡiːn/) is a city in Guadalupe County, Texas, in the United States. It is part of the San Antonio-New Braunfels Metropolitan Statistical Area. As of the 2000 census, the city population was 22,011; the July 1, 2009 Census estimate, however, showed the population had increased to 26,842. It is the county seat of Guadalupe County.
Seguin was a region once inhabited by the native Indians of Texas. Tonkawa's had predominantly lived in Seguin, camping around the Guadalupe River and other streams in the area . Eventually Spanish, Mexican, and Anglo settlements were founded in the location that would become Seguin. One of the earliest settlers and an important figure of Texas history, Jose Antonio Navarro established a ranch near Seguin. In 1831, land was granted to Umphries Branch by the Mexican government and settled by the Branch and John Newton Sowell Sr. families in 1833, in the western part of Green DeWitt's colony. Sowell was a farmer, and in 1833 he and his brothers became the first American immigrants to raise corn in future Guadalupe County.
Between 1827 and 1835 twenty-two families came to the area as part of the DeWitt Colony, and by 1833 there were forty land titles in the region, fourteen of which received grants directly from the Mexican government. In 1836, John Gladden King lived near Seguin. His farm neighbored the Sowells on the northwest and Umphries Branch on the southeast. A son, William Philip King reportedly was part of a cannon crew and was the youngest defender killed during the battle of the Alamo.