Georgetown's colors are blue and gray. The colors were selected in 1876 by the Georgetown College Boat Club (the original crew team) in honor of Georgetown students and alumni who wore the Union blue and Confederate gray in the Civil War.
As recounted in a history of the crew by Lawrence H. Cooke, distinctive colors were important in watching crew races, since fans on shore wanted to know their team's location in the race. Harvard's crimson and Penn's red and blue were already well known, but Georgetown had no such colors to call its own. A student committee declared Blue and Gray "as appropriate colors for the [Boat] Club and expressive of the feeling of unity between the Northern and Southern boys of the College" and recommended its adoption for the team.
Soon thereafter, a banner was presented to the College by the Boat Club, sewn by the girls of the nearby Georgetown Visitation school. Half blue and half gray, it bore the inscription Ocior Auro ("Swifter Than The Wind"). The banner and its colors quickly became a part of college life. Student gatherings and formal University occasions both prominently featured the colors.
By the time basketball teams were involved in varsity play, the Blue and Gray were already a Georgetown's tradition.