Hemp use in America dates to early colonial times

In the late 19th century marijuana became a popular ingredient in many over-the-counter medicines. By 1906, federal law required labeling of it in over-the-counter drugs.

The Mexican Revolution of 1910 sent a flood of Mexican refugees to the U.S., who introduced recreational marijuana use to American culture.

The drug became associated with them, and anti-immigrant fear and prejudice soon included marijuana. During the Great Depression, massive unemployment fueled fear and resentment of Mexican immigrants and increased the concern about marijuana use.

Studies at the time concluded the drug was linked with violent crime and overly sexual behavior and states began outlawing marijuana. In 1936, the famous film “Reefer Madness” showed it as a drug leading to violence and depravity.

In 1937, a federal tax effectively outlawed marijuana, the “evil weed.”

In 1944, the New York Academy of Medicine issued an extensively researched report that found that, contrary to earlier reports, marijuana did not lead to violence, insanity or sex crimes, and was not addictive.

During World War II, hemp was scarce, but was needed for war material like parachutes. The government granted deferments to men who would stay home and grow hemp for the war effort. The program was dubbed “Hemp for Victory.”

The 1950s saw strict criminal sentences for pot possession, and the countercultural 1960s saw a liberalization of use and increased use by the upper middle class.

Presidential studies confirmed the earlier New York report, that its use did not lead to violent crime or use of heavier drugs.

In 1970, federal law categorized marijuana as a drug with high abuse potential and no medical value.

By the 1970s, some states began decriminalizing marijuana or reducing penalties. But by the late 1970s, influential conservative parents groups helped start the “War on Drugs” of the 1980s. Federal law introduced harsher penalties for pot. After a decade of decreased use, marijuana use again trended upward in the 1990s, especially among teenagers.

The 1990s saw the appearance of medical marijuana laws. Oregon was one of several to pass one in 1998. Today, 23 states allow medical use of marijuana. In 2012, Washington and Colorado became the first U.S. states to legalize recreational use of marijuana. That same year, Oregon voted down a recreational marijuana measure.