Who Relinquished Claims to the Oregon Territory in the 1820s?

The question conflates two diplomatic tracks. The Monroe Doctrine (1823) declared opposition to new European colonization in the Americas but did not directly settle Oregon claims. The key 1820s agreements were:

1. Russia (1824–1825)

• Russo-American Treaty (1824): Russia agreed to 54°40' N as southern limit of its Pacific coast claims (today's Alaska Panhandle border).
• Anglo-Russian Convention (1825): Confirmed 54°40' and defined inland boundary (modern BC/Alaska border).

2. Spain (1819 → Mexico 1821 → US 1848)

• Adams–Onís Treaty (1819): Spain ceded Florida to US; US relinquished claims to Texas; boundary set at Sabine River → 42nd parallel (today's CA/OR/NV northern border). Spain retained Oregon claims north of 42°.
• Mexico inherited Spain's position (1821) but had no effective presence.

3. UK & US (1818 → 1846)

• Convention of 1818: Joint occupancy of Oregon Country (42°–54°40') for 10 years (renewed indefinitely).
• Oregon Treaty (1846): Final border at 49th parallel (Vancouver Island exception).

Answer: Russia formally gave up claims south of 54°40' in the 1820s. Spain had already set its northern limit at 42° (1819). The US/UK joint occupancy continued until 1846.