The Tennessee-class cruisers were four armored cruisers built for the United States Navy between 1903 and 1906. Their main armament of four 10-inch (254 mm) guns in twin turrets was the heaviest carried by any American armored cruiser. Their armor was thinner than that of the six Pennsylvanias which immediately preceded them, a controversial but inevitable decision due to newly imposed congressional restraints on tonnage for armored cruisers and the need for them to be able to steam at 22 knots. However, the fact their armor covered a wider area of the ship than in the Pennsylvanias and their increased firepower caused them to be seen by the Navy as an improvement.

The 3"/50 caliber gun in United States naval gun terminology indicates the gun fired a projectile 3 inches (76 mm) in diameter, and the barrel was 50 calibers long. Different guns of this caliber were used by the U.S. Navy and U.S. Coast Guard from 1900 through to 1990 on a variety of combatant and transport ship classes.