The Oregon Country was eventually made into three whole states. They were Washington, Oregon, and California is true or false ? :)

True

Explanation: In the nineteenth century, the Oregon Country was a disputed region of the Pacific Northwest of North America. The region was occupied by British and French Canadian fur traders from before 1810, and American settlers from the mid-1830s, with its coastal areas north from the Columbia River frequented by ships from all nations engaged in the maritime fur trade, most of these from the 1790s through 1810s being Boston-based. The Oregon Treaty of 1846 ended disputed joint occupancy pursuant to the Treaty

false, the oregon country was made up of oregon, washington, idaho, and british columbia

Explanation:

the  wilmot proviso  was designed to eliminate  slavery  within the  landacquired as a result of the mexican war (1846-48). fearing the addition of a pro-slave territory, pennsylvania congressman david  wilmot proposedhis amendment to the bill.