Agent Orange was not made by a single person but by a group of U.S. chemical companies under contracts with the U.S. military during the Vietnam War, using herbicides whose key components came from earlier plant‑science research.

Who made Agent Orange?

Several American companies produced Agent Orange for the U.S. Department of Defense, including:

  • Dow Chemical Company
  • Monsanto Company
  • Diamond Shamrock Corporation
  • Hercules Inc.
  • Thompson Hayward Chemical Co.
  • United States Rubber Company (Uniroyal)
  • Thompson Chemical Co.
  • Hoffman‑Taff Chemicals, Inc.
  • Agriselect

These firms manufactured large quantities of herbicides 2,4‑D and 2,4,5‑T, which were blended into what became known as Agent Orange.

How was Agent Orange developed?

  • Agent Orange was based on synthetic herbicides developed in the 1940s that could quickly kill broadleaf plants while sparing grasses and cereals.
  • In 1943, the U.S. Army contracted botanist Arthur Galston and the University of Illinois to study chemicals like 2,4‑D and 2,4,5‑T on crops, research that later fed into military defoliant programs, though Galston himself opposed their weaponization.

In other words, military planners and contractors turned agricultural plant‑control research into a powerful defoliant used at massive scale in Vietnam, rather than a single inventor consciously creating a weapon from scratch.

Information gathered from public forums or data available on the internet and portrayed here.