It is widely believed among historians that in 1920, the Danish explorer Knud Rasmussen and the Danish government challenged Canada's sovereignty over Ellesmere Island. This paper draws on a wide range of Canadian and British government files and private papers to contest this view. It demonstrates that Prime Minister Arthur Meighen and others in Ottawa were initially convinced by Vilhjalmur Stefansson that Denmark harboured territorial ambitions in the north, but most realised in the spring of 1921 that they had been mistaken. However, one civil servant, J. B. Harkin, stubbornly maintained his belief in the Danish threat. After Mackenzie King's Liberals came to power, Harkin was able to obtain a hearing for his views. It was largely due to Harkin's persistence that the first Eastern Arctic Patrol went north in 1922.