Before Dallas was settled by Europeans, a southeastern Native American tribe called the Caddo inhabited the area. Dallas was part of the Spanish Viceroyalty of New Spain in the 16th century. The area was also claimed by the French at one point, but the Adams-Onís Treaty in 1819 officially placed Dallas within Spanish territory. As a result of this treaty, the northern boundary of the Red River became "New Spain."
Dallas remained under Spanish rule until 1821. When Mexico declared independence from Spain, Dallas became part of the Mexican state called Coahuila y Tejas. In 1836, the Republic of Texas broke away from Mexico and remained an independent country for almost ten years.
In search of a trading post to serve Native Americans and settlers, a man named John Neely Bryan surveyed Dallas in 1893. Bryan was drawn to the Caddo trails and Preston Trail that was planned to run near the ford. He established a trading post called Bryan's Bluff along the north-south route along the ford. In 1845, the United States annexed Texas and Bryan's Bluff became more important. Bryan returned home to Arkansas after surveying Dallas. While he was gone, a treaty was signed removing all Native Americans from Northern Texas. When Bryan returned, half of his customers were removed from the area. As a result of this, he decided to create a permanent settlement rather than a trading post. According to the official historical marker, Bryan named this settlement Dallas after Vice President George M. Dallas of Philadelphia, Pennsylvania.
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