“Federal Standard 595—Colors Used in Government Procurement” has its roots in World War I, when in 1918 Bulletin No. 90 of the General HQ of the American Expeditionary Force established a color identified as “olive drab” as the official shade for tactical vehicles, though what exactly those words indicated was a subject of some confusion. In 1917, the manual for the Quartermaster Corps had defined olive drab as a combination of ochre and black pigments, though it did not mention a specific ratio, nor did it indicate which manufacturer’s pigments were best suited for the job.