The name Micronesia is derived from the Greek words mikros, "small," and neso, "island." Until recently, the many distinct languages of the Micronesian islands existed only in oral form. Thus, much of the early history of these islands had to be derived from archaeological artifacts. It is thought that more than 3,000 years ago, Austronesian speaking Micronesian people entered the Pacific from Southeast Asia. These seafaring people probably first settled in the Marianas (Guam and Saipan) and then the Western Carolines, including Palau and Yap. Later, migrations from the southern Melanesian islands brought settlers to Kosrae, Chuuk, and Pohnpei. The "outer islands" of Micronesia were likely settled later, as their languages are dissimilar to those of the main islands. Micronesians are known as great sea voyagers and sailed huge outrigger canoes over distances of thousands of miles, using traditional navigation techniques, dependent on knowledge of the movements of currents, swells, winds, and birds. Early Micronesians lived a subsistence lifestyle based on fishing, gathering, and agriculture. Legends of ancient civilization in the Caroline Islands tell of an ancient empire, about which little is known. The remnants of magnificent stone fortresses constructed from basalt pillars in Pohnpei (Nan Madol) and in Kosrae (Lela Ruins) are thought to date back to A.D. 400. Yapese stone money (stone discs as large as 12 feet in diameter that can weigh up to 12 tons) was mined as far away as Palau and transported by canoe to Yap. Islands in the archipelagoes known as Micronesia were among the first in the Pacific to be "discovered" by European explorers of the 16th century. The islands were grouped into three categories: the Marshall Islands, the Eastern Caroline Islands (Kosrae, Pohnpei, and Chuuk) and the Western Caroline Islands (Yap and Palau). The first known European contact dates back to 1521, during Ferdinand Magellan's quest to find a trade route to the Spice Islands of the east, traveling west from Spain. The Spaniards developed an indirect trade route to Asia: across the Atlantic to South America, across South America via land, and onward into the Pacific. In the 18th and 19th centuries, whalers, traders, and missionaries found their way to the islands. The missionaries succeeded in creating what are today entirely Christian societies on all the major islands and some outer islands. Micronesians retain little memory of earlier belief systems. The islands of the FSM and Palau share similar colonial histories under Spain, Germany, Japan, and the United States. Spanish influence in Micronesia expanded in the 19th century, but following its defeat in the Spanish- American War, Spain sold Palau and most of the Caroline Islands (which later became FSM) to Germany in 1899. The Germans were interested in the islands to support trade in coconut products. Their use of forced labor on the island of Pohnpei culminated in the assassination of the German governor by a young Micronesian. Many Pohnpeian men were then exiled to Palau; other Micronesian men were transported from the outer islands of Pohnpei and Chuuk. The Germans deserted Micronesia in World War I, which allowed an easy takeover by the Japanese. Japan built large military bases on some of the islands and developed sugar mills in the Marianas; bauxite and phosphate mines in Palau; and fishing and shell production throughout the region. The Japanese encouraged emigration to Micronesia, and Micronesians were used as low-level manual laborers.