The U.S. military appears to have first used ghillie suits in the Vietnam War era, when American snipers began adopting crude burlap-based camouflage; broader military use traces back earlier to the British Lovat Scouts in World War I.

What the record suggests

  • The earliest known military users of ghillie suits were the British Lovat Scouts during the Second Boer War, with World War I marking their formal sniper use.
  • For the U.S. military specifically, available sources point to Vietnam-era sniper use as the first widespread adoption, rather than an earlier formal issue.
  • So the safest answer is: U.S. use began in Vietnam, but the ghillie suit itself predates that by several decades.

Quick takeaway

If you mean “when did American forces first use it,” the best-supported answer is the Vietnam War period.

TL;DR

The ghillie suit was not first used by the U.S. military; it was first used militarily by British units in the early 1900s, while U.S. military use shows up later, in Vietnam.