Treaty instrument, signed by nine states (Norway, the United States of America, Denmark, France, Italy, Japan, the Netherlands, Great Britain and Ireland - later expanded to presently include 42+ signatories) at Paris on February 9, 1920. The treaty established Norwegian sovereignty over the Svalbard archipelago (located between 74° N 10° E and 81° N 35° E), but simultaneously instituted a number of restrictions on the exercise of that sovereignty.

By the terms of the treaty, Svalbard must remain a demilitarised zone, and signatories to the treaty are granted a number of rights, including access to port and airfield facilities, as well as commercial and mining access. Furthermore, Svalbard is a nearly tax free zone, with only a local municipal tax being allowed.

The treaty took formal effect on August 14, 1925, at which time Svalbard (hitherto a no man's land) became an official part of the Kingdom of Norway. Norway's flag was flown, and a local governor (Sysselman) was installed at Ankershamn (later at Longyearbyen). Local place names were changed to Norwegian names:

• Advent Bay became Longyearbyen
• King's Bay became Ny Ålesund
• Green Harbour became Ankershamn