Which Capital Lies East of the Rockies? Neither Sacramento Nor Columbus

Neither.

• Sacramento, CA – West of the Rocky Mountains (in the Central Valley).
• Columbus, OH – Far east of the Rockies (Midwest, ~1,000 mi from the Front Range).

Capitals Actually East of the Rockies

All U.S. state capitals except those in the Mountain West (Denver, Helena, Boise, Salt Lake City, Cheyenne, Santa Fe, Phoenix, Carson City) lie east of the Rockies. Examples: Lincoln (NE), Topeka (KS), Oklahoma City (OK), Austin (TX), Des Moines (IA), St. Paul (MN).

The Rocky Mountains form the Continental Divide; "east of the Rockies" includes the Great Plains, Midwest, and everything to the Atlantic.