The Darien scheme was an unsuccessful attempt, backed largely by investors of the Kingdom of Scotland, to gain wealth and influence by establishing New Caledonia, a colony in the Darién Gap on the Isthmus of Panama, in the late 1690s. The plan was for the colony, located on the Gulf of Darién, to establish and manage an overland route to connect the Pacific and Atlantic Oceans. The backers knew that the first sighting of the Pacific Ocean by Vasco Núñez de Balboa was after crossing the isthmus through Darién. The expedition also claimed sovereignty over "Crab Isle" (modern day Vieques, Puerto Rico) in 1698, yet sovereignty was short-lived. The attempt at settling the area did not go well; more than 80 percent of participants died within a year, and the settlement was abandoned twice.
There are many explanations for the disaster. Rival claims have been made suggesting that the undertaking was beset by poor planning and provisioning; divided leadership; a lack of trade with local indigenous tribes or neighbouring Dutch and English colonies; epidemics of tropical disease; widespread opposition to the scheme from commercial interests in England; and a failure to anticipate a military response from the Spanish Empire. It was finally abandoned in March 1700 after a siege by Spanish forces, which also blockaded the harbour.