During the mid-19th century, cartography was often as potent a tool of sovereignty as heavy artillery. In 1844, a geopolitical misunderstanding unfolded near Lulu Island, located in the delta of the Fraser River in present-day British Columbia. Conflicting territorial claims between British colonial authorities and American trading factions were exacerbated by grossly inaccurate map surveys.
British hydrographers had mapped the mudflats and channels of the Fraser delta using rough soundings, while private American surveyors pushed competing boundary lines based on alternative river channel definitions. When an American merchant vessel attempted to establish an unlicensed trading post on Lulu Island relying on an aggressive Oregon Territory map interpretation, the Hudson's Bay Company and local Royal Navy officers mobilized to expel them. Warships converged on the mudflats, preparing for a forceful eviction over what both sides believed was their legally charted territory.
The standoff intensified until soundings taken on-site revealed that the channel depicted on the American map didn't even exist at low tide, stranding the merchant vessel on mud banks. Realizing the brinkmanship was based on fictitious geography, both commanders stood down to avoid an accidental war. The near-miss underscored how flawed 19th-century maps could bring imperial superpowers to the edge of military conflict over muddy delta mudflats.