Miguel Hidalgo y Costilla declared Mexico's independence from Spain on September 16, 1810.In 1819, the United States ceded its claim to the land south and west of the Arkansas River to Spain with the Adams-Onís Treaty, at the same time purchasing Florida.
The Provisional Government of the Territory of Jefferson was organized on October 24, 1859, but the new territory failed to secure federal sanction. The Territory of Colorado was a historic, organized territory of the United States that existed between 18.The Provisional Government freely administered the region despite its lack of official status until the U. Its boundaries were identical to the current State of Colorado.During the period 1832 to 1856, traders, trappers, and settlers established trading posts and small settlements along the Arkansas River, and on the South Platte near the Front Range.Prominent among these were Bent's Fort and Fort Pueblo on the Arkansas and Fort Saint Vrain on the South Platte.News of this discovery soon spread and precipitated the Pike's Peak Gold Rush.
An estimated 100,000 gold seekers flocked to the region over the next three years.
Westward expansion brought European settlers to the area and Colorado's recorded history began with treaties and wars with Mexico and American Indian nations to gain territorial lands to support the transcontinental migration.
In the early days of the Colorado gold rush, Colorado was a Territory of Kansas and Territory of Jefferson.
Juan de Oñate who lived until 1626, founded what would become the Spanish province of Santa Fé de Nuevo México among the pueblos of the Rio Grande on July 11, 1598.
In 1706 Juan de Ulibarri claimed the territory of Colorado.
On June 22, 1850, a wagon train bound for California crossed the South Platte River just north of the confluence with Clear Creek, and followed Clear Creek west for six miles.