Alexander McDowell McCook was a career United States Army officer and a Union general in the American Civil War.

The Fighting McCooks were members of a family of Ohioans who reached prominence as officers in the Union Army during the American Civil War. Two brothers, Daniel and John McCook, and thirteen of their sons were involved in the army, making the family one of the most prolific in American military history. Six of the McCooks reached the rank of brigadier general or higher. Several family members were killed in action or died from their wounds. Following the war, several others reached high political offices, including governorships and diplomatic posts.