In a Jan. 18 text message to the prime minister of Norway, Donald Trump asked why Denmark has a "right of ownership'" over Greenland? A week earlier, Trump's adviser Stephen Miller had asked on CNN, "By what right does Denmark assert control over Greenland? What is the basis of their territorial claim?"
These questions sounded provocative -- almost radical. Yet there is a clear historical answer, one that has been settled for nearly a century.
Greenland's political status is not an accident of modern geopolitics or a recent contrivance. Denmark's sovereignty rests on centuries of settlement, administration, diplomatic recognition and ultimately international adjudication. Whatever one thinks of Trump's renewed interest in the island, the idea that Greenland's ownership is somehow unresolved ignores both history and international law.
The first Europeans to settle Greenland were Norse colonists from Scandinavia who arrived around the year 1000, led by Erik the Red. By the 15th century, those colonies had disappeared, leaving Greenland once again under Indigenous control.
When Europeans reestablished contact in the 16th century, Danish authorities believed incorrectly that descendants of the medieval Norse settlers might still be present. In 1721, a Danish-Norwegian expedition led by the missionary Hans Egede arrived in Greenland. A few years later they founded a settlement that would eventually become Nuuk, Greenland's capital.
Over the following centuries, Denmark maintained small settlements along Greenland's coast and exercised control through trade, administration and religious missions. In the 18th and 19th centuries, Denmark asserted authority over western Greenland and enforced a state-sponsored trade monopoly. American merchants sometimes traded with the island, but Denmark required its permission.
An 1826 trade treaty between the U.S. and Denmark specifically excluded trade with Greenland, where Denmark maintained tight restrictions. Denmark’s 1721 settlement and this limited American trade is presumably what Trump was referring to when he said that “a boat landed there hundreds of years ago, but we had boats landing there, also.”
The island’s status was not lost on American officials in the 19th century. When Secretary of State William Seward commissioned an 1868 report that recommended the U.S. consider acquiring Greenland, the proposal assumed Danish ownership. Seward did not treat Greenland as terra nullius (land belonging to no one) but as a possession that would have to be purchased from Denmark.
The idea went nowhere, in part because Congress was already uneasy about Seward’s recent purchase of Alaska and deeply hostile to President Andrew Johnson, who was then facing impeachment.
American interest in Greenland persisted. In the late 19th and early 20th centuries, American expeditions mapped large portions of the island that lay beyond Denmark’s settlements. After exploring northern Greenland in 1891-92, American explorer Robert Peary finally established that Greenland was an island, not connected to Canada or some polar continent. He later argued that the U.S. should acquire Greenland for strategic reasons.
In the 1910s, America’s ambassador to Denmark explored the possibility of a territorial exchange that would have transferred Greenland to U.S. control. But when the United States agreed to purchase the Danish West Indies (today’s U.S. Virgin Islands) in 1916, President Woodrow Wilson calculated that the Caribbean islands were important to defending the new Panama Canal. Greenland was not. As part of the purchase agreement, the United States formally acknowledged Danish sovereignty over the whole of Greenland.
"The United States of America will not object to the Danish Government extending their political and economic interests to the whole of Greenland," wrote Secretary of State Robert Lansing in a declaration accompanying the purchase treaty. This U.S. statement strengthened Denmark's international position regarding sovereignty over the entire island.
American recognition proved decisive. In 1921, Denmark issued a decree that all of Greenland fell under its sovereignty. Norway objected, arguing that Denmark’s authority extended only to areas it had actively settled. In 1931, Norway went so far as to claim a portion of eastern Greenland, naming it “Erik the Red’s Land.”
The dispute was resolved not by force, but by law. In 1933, the Permanent Court of International Justice (the predecessor to today’s International Court of Justice) ruled that Denmark’s claim to all of Greenland was valid. Among the factors cited was international recognition, including the United States’ explicit acceptance of Danish sovereignty in 1916. From that point on, Greenland’s legal status was settled.
After World War II, President Harry Truman offered to purchase Greenland, again acknowledging that Denmark had the right to sell or refuse. Denmark declined but allowed the U.S. to maintain military bases there. That arrangement continues today.
So when Trump and Miller ask by what right Denmark controls Greenland, the answer is straightforward: by centuries of settlement and administration; the absence of competing claims; explicit recognition from other major powers -- including the United States --; and a definitive ruling from an international court.
That history makes today’s rhetoric sound less like bold geopolitics than selective amnesia. Under international law, sovereignty is established by continuity, not by asking provocative questions. Greenland’s status is not unsettled. Only our memory of how it was settled seems to be.
Mark Kawar is the author of the forthcoming book "America, but Bigger: Near-Annexations from Greenland to the Galápagos."