 The earliest known contact with Europeans occurred in 1521, when Spanish ships landed in the Marianas.The term "Micronesia" is usually attributed to Jules Dumont d'Urville's use of it in 1832, but Domeny de Rienzi had used the term a year previously.Micronesia is a region that includes approximately 2100 islands, with a total land area of , the largest of which is Guam, which covers .