The Battle of the Binary Stars, 2256

The opening shot in the other infamous war in Federation history—its war with the Klingons in the mid 2250s—the Battle of the Binary Stars saw eight Federation vessels lost and thousands of Starfleet personnel killed and injured. At the time it was only the second major engagement Starfleet had had with the Klingons after a period of cold war and little interaction for both powers in the century prior, but it set the stage for a war that would claim the lives of 100 million Federation citizens.