IF the words of 13th-century Scottish poet and prophet Thomas the Rhymer can be taken at face value, Scotland and England were cultivating simple agricultural strains of cannabis sativa at the time of Bruce and Wallace. Thomas imagined that “Scotland and England shall be one” when “Hemp is come and also gone”, lines subsequently interpreted as a prophecy about the British Union.

Thomas was wrong; by the mid-18th century, cannabis production in Scotland had become a highly regulated industry bound by specific agriculture laws and led by a highly dedicated workforce. Weed fields were everywhere.

Robert Burns, who confessed in 1789 that he would sit down to write “as I would sit down to beat hemp”, mischievously suggested that farmers who grew hemp a certain way while performing a certain ritual would see (over their left shoulder) the apparition of a human being “in the attitude of pulling Hemp”.

Farmers were told (in 1739) that “every person who shall sell” hempseed in Scotland “shall, together with the parcel, deliver to the buyer, in writing, an account of the parcel” and its weight/volume, the name of the farm and the year the crop was grown. Scottish hemp farmers weren’t permitted to grow, store, trade or sell “any mixed or damnified” hemp seed.

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The Society for the Encouragement of Arts, Manufactures and Commerce expressed a strong desire (in 1802) to promote and invest in Scottish cannabis production, offering gold medals and 50 guinea grants to farmers processing larger volumes of industrial hemp “for the use of our navy”. Their campaign specifically aimed to enhance “Scotland’s Culture of Hemp”.

An 1815 discussion about cannabis stated that “a small quantity of hemp was raised by every farmer in Scotland, for the use of his own farm” in the distant past, but was “scarcely cultivated in Scotland” in the early 19th century, despite being a massive international industry just 15 years later.

Industrial cannabis had already been bred for thousands of years to provide rope and fabric long before it reached these islands. Hemp can be grown in northern climates because it gets harvested before the low temperatures and unlimited dampness destroys the crop.

Even if hemp contained enough psychoactive compounds for recreational or medical use, all cannabis varieties grown in Scotland will generally die from exposure long before they fully flower.

Pollen evidence from specific sites strongly indicates that large quantities of hemp were being cultivated for industrial purposes in Scotland between 985 and 1270, and again around 1460. One site was probably producing significant volumes of cannabis for a century or more after 1593.

The British government at first actively encouraged cannabis cultivation in Scotland, which was being carved into a profitable home farm for the entire island and beyond. Less than a decade after the Jacobite Rebellion of 1745, the British ruling class passed a hemp and flax act “for encouraging and improving the manufacturing of linen in the Highlands of Scotland”. After 1787, Britain awarded funds for cannabis cultivation in Scotland before abruptly withdrawing financial support in 1833.

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Scotland’s weed needs were briefly improved when forgotten Scottish inventor Robert MacPherson created a device called “The Foot Maceine” for “Breaking & Beating Flax & Hemp” in 1763 – a remarkably early innovation predating virtually every significant breakthrough of the Industrial Revolution.

Before 1832, almost 20,000 people were employed in Scotland’s “linen and hemp” industry, almost twice the amount working with the same materials in England. In 1861 there were still only five “hemp factories” in the UK, but they had increased to 61 different factory sites by 1874, 12 of which were in Scotland. At different times in the 19th century, almost half of all US cannabis imports came from Scotland.

Farmers could even claim a cash reward from the Society of Arts if they produced certified evidence of their grow “along with 14lbs of the hemp […] delivered to the Society” by January 1803, as long as it hadn’t been “steeped or watered in any bog-hole” or mixed with “what is left of the former year”.

Seems fair.