400s BC.: Spartan Greeks use sulfur fumes against enemy soldiers. \n\n 1346: Crimean Tatars catapult plague-infected corpses into Italian trade settlement. \n\n 1500s: Spanish conquistadors use biological warfare used against Native peoples. \n\n 1763: British Gen. Jeffrey Amherst orders use of smallpox blankets against Native peoples during Pontiac's Rebellion. \n\n 1800s: Blankets infected with smallpox deliberately given to Native Americans, causing widespread epidemics. \n\n 1907: Hague Convention outlaws chemical weapons; U.S. does not participate. \n\n 1914: World War I begins; poison gas produces 100,000 deaths, 900,000 injuries. \n\n 1920s: Britain uses chemical weapons in Iraq "as an experiment" against Kurdish rebels seeking independence; Winston Churchill "strongly" backs the use of "poisoned gas against uncivilised tribes." \n\n 1928: Geneva Protocol prohibits gas and bacteriological warfare; most countries that ratify it prohibit only the first use of such weapons. \n\n 1935: Italy begins conquest of Abyssinia (Ethiopia), using mustard gas. \n\n 1936: Japan invades China, uses chemical weapons in war; German chemical labs produced the first nerve agent, Tabun \n\n1939: World War II begins; neither side uses bio-chemical arms, due to fears of retaliation in kind. \n\n 1941: U.S. enters World War II; President Roosevelt pledges U.S. will not be first to use bio-chemical weapons. \n\n 1943: U.S. ship damaged by German bombing raid on Bari, Italy, leaks mustard gas, killing 1000. \n\n 1945: Germans use Zyklon-B in extermination of civilians. Japanese military discovered to have conducted biological warfare experiments on POWs, killing 3000. U.S. shields officers in charge from war crimes trials, in return for data. Soviets take over German nerve gas facility in Potsdam. The Nazis had stockpiles of nerve gas, against which the Allies had no defenses, and had also been working on blood agents. \n\n1947: U.S. possesses germ warfare weapons; President Truman withdraws Geneva Protocol from Senate consideration. \n\n 1949: U.S. dismisses Soviet trials of Japanese for germ warfare as "propaganda." Army begins secret tests of biological agents in U.S. cities. \n\n 1950: Korean War begins; North Korea and China accuse U.S. of germ warfare--charges still not proven. San Francisco disease outbreak matching Army bacteria used on city. \n\n 1951: African-Americans exposed to potentially fatal simulant in Virginia test of race-specific fungal weapons. \n\n 1952: German chemical weapons researcher Walter Schreiber, working in Texas, exposed as a perpetrator of concentration canp experiments, and flees to Argentina. \n\n1956: Army manual explicitly states that bio-chemical warfare is not banned. Rep. Gerald Ford wins policy change to give U.S. military "first strike" authority on chemical arms. \n\n1959: House resolution against first use of bio-chemical weapons is defeated. \n\n 1961: Kennedy Adminsitration begins hike of chemical weapons spending from $75 million to more than $330 million. \n\n1962: Chemical weapons loaded on U.S. planes during Cuban missile crisis. \n\n 1966: Army germ warfare experiment in New York subway system. \n\n 1968: Pentagon asks for the chance to use some its arsenal against civil rights and anti-war protesters to demonstrate the "efficacy" of the chemicals. "By using gas in civil situations, we accomplish two purposes: controlling crowds and also educating people on gas," said Maj. Gen. J.B. Medaris. "Now, everybody is being called savage if he just talks about it. But nerve gas is the only way I know of to sort out the guys in white hats from the ones in the black hats without killing any of them." \n\n1969: Utah chemical weapons accident kills thousands of sheep; President Nixon declares U.S. moratorium on chemical weapons production and biological weapons possession. U.N. General Assembly bans use of herbicides (plant