In 1939, US President Franklin D. Roosevelt told members of an Antarctic expedition to claim some Antarctic territory. Members of this expedition and later ones seemed to do so, but no official claims were made before 1959, when the Antarctic Treaty System was set up. Some maps in the United States have shown this as US territory. The Defense Department of the US Government has also said that there was a solid basis for a claim for the territory. This was because of the activities there before 1959. 