Shortly after the establishment of Cosquer, delegates from the English settlement Freetown sailed to New Hastings, and met with Edward Radcliffe, the first settler of Atlantis. The Freetown representatives demanded that New Hastings and Freetown join together to expel the Bretons. Radcliffe, who felt indebted to Kersauzon for discovering Atlantis, refused. Radcliffe went one step further, warning the Freetown delegates that if they attacked Cosquer, New Hastings would attack Freetown.
Cosquer became a French settlement after Brittany was absorbed by France in 1532. After the French and Spanish War, it became a British possession, until it joined the successful Atlantean War of Independence, when it became part of the United States of Atlantis.