When and where did weed as a narcotic enter the New World?
It [was] brought to the Americas by the Portuguese, who took it to Brazil, and again by the British, who took it to Jamaica. In both cases, it was used to pacify slaves.
How did people there go from seeing weed as a tool of slavery to seeing it as a fun drug?
Well, it doesn't take a big leap of logic. You had cannabis being grown by the British East India company. [They] grew it in Bengal and India and exported it to Guyana, South Africa, and Jamaica. [They] taxed it heavily and encouraged its plantation well after slavery ended there.
It was sold in company stores in Jamaica [for instance] well up into the 20th century. Slave-like conditions persisted in the sugar cane fields [there] well into the 20th century, when there was this widespread mechanization of sugar cane production. Until the production of sugar cane ended, I think people were smoking cannabis for much the same reasons. It just became part of Jamaican culture [and in other places it was grown and smoked from the slave-era on].
There were [also] large Indian populations in the Caribbean. Indentured Indian workers who worked alongside blacks were probably another vehicle by which [smokeable, recreational marijuana] was brought into [the Caribbean, for example] at the time.
Getting back to the United States proper, how did weed-the-narcotic make its jump from South America and the Caribbean into America, and when?
The introduction of smokeable cannabis to the US largely begins after the Mexican Revolution of 1910 to 1911. There were a number of refugees crossing the border from the violence of the revolution at the time, and they brought smokeable cannabis with them. There had been a long tradition of smokeable cannabis in Latin America [after its introduction to the region via plantations] and networks of marihuaneros [pot growers] in Spanish-speaking countries.
The immigrants fleeing the violence in Mexico brought cannabis into the southwestern US, particularly Texas. It was there that the first backlash against cannabis began. El Paso became the first city to have an ordinance against it in 1914.
What impact did that have on the way we look at pot today?
These Mexican roots of American smokeable cannabis are important because it was known as a colored-people's drug well into the 1960s when the baby boom discovered it and white college kids began to smoke it and it lost its racial connotations.
There was also cannabis being brought into places like New Orleans by sailors and sometimes by immigrants from the Caribbean [around the same time]. The black community also began to pick up on cannabis, so that reinforced this racial stereotype that brown and black people smoke cannabis and white people did not.