 The city had a population of 56,364 at the 2010 census, up from 53,248 at the 2000 census.The city is named after Arcadia, Greece.For over 8,000 years the site of Arcadia was part of the homeland of the Tongva people ("Gabrieliño" tribe), a Californian Native American tribe whose territory spanned the greater Los Angeles Basin, and the San Gabriel and San Fernando Valleys.