There are hundreds of indigenous groups in South America. Each has its own indigenous language and culture, as well as mythology. It is thought that most if not all of these peoples crossed into the Americas via the land mass that later became the Bering Strait. There is indication of South American agriculture by 6500 B.C.E. As permanent settlements developed over the next millennia, so did mythology. In the time just before the arrival of the Spanish conquistadors, led by Francisco Pizarro in 1526, South America, at least in the Andean region, was dominated by a people known as the Inca.