Which came first Texas the Oregon country or the land ceded by Mexico?

The Oregon Country was explored and claimed by various nations in the early 19th century, while Texas declared independence from Mexico in 1836 and became a Republic. The land ceded by Mexico to the United States came after the Mexican-American War, formalized in the Treaty of Guadalupe Hidalgo in 1848. Therefore, the Oregon Country was claimed first, followed by Texas, and then the land ceded by Mexico.