Texas claimed the Rio Grande as its southern border. Mexico said the Nueces River, to the north, should be the border. The dispute simmered until Dec. 29, 1845, when the U.S. annexed the Lone Star ...

A senior Texas official has asked the Trump administration and federal authorities at the southern border to help the state take back control of two islands in the Rio Grande that Mexican cartels have ...

Fronton Island is the disputed territory that sits within the Rio Grande River at the southern border. Both Texas and Mexico have made conflicting claims regarding the islands' ownership.