Plaster War of 1820

The Plaster War of 1820 was not a war in the usual sense, but this little-known period in our history featured extraordinary showdowns between gypsum smugglers and the man tasked with ending their illegal trade with the US. Here is the story:

When gypsum mining started in Nova Scotia in the 1770s, it was done by farmers who extracted it from their farms, hauled it by horse and cart to shipping points near Windsor, Hants County, and sold it to local traders. The gypsum was then exported to the east coast of the United States for use as fertilizer because gypsum fixes alkaline (high pH) soil. It was ground up and spread on farm fields to increase crop yields.

However, not all the gypsum, which was then called plaster because it is also a key ingredient in Plaster of Paris, was sold to legitimate traders. The farmers often shipped their gypsum themselves or had family members or other small boats do it. Plastermen – the name given to both the men who smuggled gypsum and to their boats - carried the rock to Passamaquoddy Bay, which is between New Brunswick and Maine. There it was either lightered ashore in small vessels and dumped into piles on shore, or transferred directly to American vessels, either by small boats or by ships coming alongside each other, preferably under cover of night.

Passamaquoddy Bay was a hotbed of smuggling activity in the early 1800s. It is estimated that in 1794, approximately 100 tons of gypsum were exported via Passamaquoddy; by 1802 about 13,000 tons, by 1806, 50,000 tons, and by 1820 over 100,000 tons. The combination of smuggled and legitimate gypsum likely made it British North America’s most valuable export to the US in the early 1800s, according to historians.

In exchange for the gypsum, the smugglers brought back flour, blankets, tobacco, rum, molasses, tea and other goods that were needed on this side of the border.

British authorities sometimes tried to stamp out the smuggling because the illicit goods were, of course, traded without any customs duty on them, and the Crown wanted its taxes.

The problem persisted for years and in 1816-17, the New Brunswick and Nova Scotia colonial governments passed complementary laws that tried to prevent landing gypsum along known smuggling routes in the US or in the provinces. The goal was to have gypsum exports controlled by legitimate merchants and shipowners who would pay the duties. However, the Americans retaliated with a law of their own and the effort failed.

In 1820, the New Brunswick government, pushed by Saint John merchants, passed a new law that appointed a "preventative officer" with wide powers to control the gypsum trade. Stephen Humbert of Saint John was appointed to the role.

Humbert was a merchant, politician and militia officer but his best qualification for his new job was perhaps that he was a smuggler himself. Smuggling was a way of life in border communities in that era, widely practiced and supported by all levels of society. It helped both rich and poor make a living and provided goods that were otherwise unavailable.

His new job caused Humbert to become the most hated man in the region, subjected to a series of extraordinary humiliations and attacks that would be shocking to us law-abiding, mild-mannered Canadians today.

The first humiliation came when Humbert and his son John, who served as Humbert’s deputy, boarded a vessel, the Mary, to ensure its compliance with the new plaster law. The Nova Scotian ship had taken refuge from a storm on Partridge Island in the mouth of Sant John harbour. The ship’s captain refused to cooperate by providing his ship's papers, and the Humberts took the vessel into custody.

Humbert left his son John and a guard on board and then set sail for Passamaquoddy to attend to other duties. That same night, the smugglers overwhelmed John and the guard and sailed off with them as their prisoners. The smugglers did not harm them but they left John Humbert and the guard near Annapolis, Nova Scotia. Out of their jurisdiction, lost and without nearby help, they had to begin the long and embarrassing process of finding their way home.

At the same time, the elder Humbert was also in some trouble. Within minutes of anchoring his vessel in Passamaquoddy Bay, with it’s a distinctive flag that conveyed his role as an anti-smuggling official, a sailor on a nearby boat fired a musket at Humbert's craft. The shot missed, but it had come from American waters, outside of Humbert's jurisdiction, so he could do nothing. Humbert later learned that James McArthur, the captain of the ship, challenged his crew to fire at Humbert’s vessel, promising to buy a drink for anyone who did.

Humbert tried to intercept vessels but found it impossible in the face of armed resistance. When he approached suspected plastermen, the crews appeared on deck with muskets to keep him away. Other times Humbert had boats full of men pursuing him, and he reported that all the plastermen had armed themselves, some with cannon, an act he considered "open rebellion."

When Humbert approached dozens of smuggling boats off Lubec, Maine, in mid August 1820, crewmen from seven or eight of them opened fire with muskets, forcing him to anchor. The following day Humbert spied two plastermen approaching Lubec through the difficult western channel. He pursued and forced one of the smugglers aground on the American shore and boarded the other just a few feet offshore. A crowd of about sixty Americans, in sympathy with the smugglers, gathered onshore and helped to force Humbert off the smuggling craft. Throwing rocks and using tools such as axes, the crowd forced Humbert to retreat after the rioters stabbed one of his men in the arm.

The next day Humbert watched while ten plastermen sailed from Lubec, lashed together like an enormous raft. Humbert did not have a force strong enough to match the smugglers, and the British navy did not prioritize the anti-smuggling effort enough to give him one, so he could do little to oppose the smugglers’ tactics.

Even colonial customs officers frustrated Humbert’s attempts to stop the smuggling because they pocketed bribes in exchange for letting it take place. New Brunswick's Council and Nova Scotia's Legislative Assembly launched investigations into customhouse corruption in 1820 and produced some startling results. For example, Windsor produced only eighteen shillings in customs revenue for the Crown between 1816 and 1819, but it produced an estimated £3,000 in fees that went directly into customs officials' pockets.

Not surprisingly, customs officers opposed regulating the plaster trade and did not help Humbert.

On September 29-30, 1820, Humbert tried to seize two plastermen. The problem was that the vessels were in Lubec harbour – beyond his jurisdiction – so the smugglers had an American magistrate issue a warrant for his arrest. A boat with a magistrate and a deputy sheriff put off from shore with the intent of arresting Humbert so he retreated to British waters with one of the smuggling boats. However, the smugglers stole it back by 4:00 a.m. the next day.

Humbert returned to Saint John and admitted his failure. Adding insult to injury, the smugglers lodged complaints against him, falsely claiming he was smuggling American goods into New Brunswick in that period.

The New Brunswick Assembly quietly repealed the Plaster Act early in 1821. The Plaster War was over.

Gypsum is still used as fertilizer and in plaster but its main use now is in wallboard/drywall. Gypsum is 21% water on the molecular level and its moisture slows the spread of fire and saves lives.

Thanks to historian Joshua Smith whose dissertation provided most of the material for this story (