Island group, Papua New Guinea, southeast of New Guinea .
Stretching for more than 100 mi (160 km), it occupies 10,000 sq mi (26,000 sq km) of the South Pacific Ocean. It has nearly 100 islands; the largest are Misima, Tagula, and Rossel. It was visited by the Spanish in 1606 and was named after Louis XV of France in 1768. Occupied by Japanese forces in 1942, the islands are near the site of the Battle of the Coral Sea .