By the time the Civil War began, opposing forces in Bleeding Kansas and Missouri had been killing each other for five years. And were very good at it.

The Nazi Einsatzgruppen began the World War II’s most closely guarded operation: the annihilation of the Jews.

The AC-47 gunship proved the concept of the aerial gunship as a close support weapon in the skies over Vietnam.

His army reduced to shambles, Confederate General Jubal Early waited uneasily at Waynesboro, Virginia, to do battle one last time with Phil Sheridan.