On October 2nd 1835 the Texas Revolution, also known as the Texas War of Independence, began.
The conflict was started by colonists, most of whom had immigrated from the United States, against the Mexican government. Mexico had recently become independent for Spain, and had taken many of the lands that formerly made up New Spain, which included Texas.
The US colonists, and many Americans, thought that Texas should be independent of Mexico, and should probably been a part of the United States. The war between the colonists and Mexico resulted in the establishment of the independent Republic of Texas, which later was admitted to the US as a state.
Image: By William Henry Huddle (1847 – 1892) [Public domain], via Wikimedia Commons