The 1st Infantry Division (1ID) is a combined arms division of the United States Army, and is the oldest continuously serving division in the Regular Army.[5] It has seen continuous service since its organization in 1917 during World War I.[6] It was officially nicknamed The Big Red One (abbreviated BRO[2]) after its shoulder patch[6] and is also nicknamed The Fighting First.[6] The division has also received troop monikers of The Big Dead One and The Bloody First as puns on the respective officially sanctioned nicknames.[7] It is currently based at Fort Riley, Kansas.