Directed federal agencies to rename the Gulf of Mexico the 'Gulf of America' and restore the name 'Mount McKinley' to Denali.
How it happened
Signed Inauguration Day; the U.S. Board on Geographic Names updated federal usage.
Documented impact
Mixed impactsubstantiated
Adopted in U.S. federal usage and some map providers; not recognized internationally.
Federal databases and some mapping services adopted the change for U.S. users; Mexico and international bodies retained 'Gulf of Mexico.' A press-access dispute over the name drew litigation.
Sources
Every claim above links to its source. Primary record and cited reporting: