Most archaeological, linguistic, cultural, and genetic evidence tends to support a western origin for Polynesians, from Island Southeast Asia, using sophisticated multihull sailing technologies and navigation techniques during the Austronesian expansion. Heyerdahl's full hypothesis of a South American origin of the Polynesian peoples is generally rejected by scientists today.

This idea has recently received support from statistical analysis of genetic evidence of contact between South America and Polynesia. Although the expedition carried some modern equipment, such as a radio, watches, charts, sextant, and metal knives, Heyerdahl argued they were incidental to the purpose of proving that the raft itself could make the journey. His aim in mounting the Kon-Tiki expedition was to show, by using only the materials and technologies available to those people at the time, that there were no technical reasons to prevent them from having done so. Heyerdahl believed that people from South America could have reached Polynesia during pre-Columbian times. Kon-Tiki is also the name of Heyerdahl's book, the Academy Award–winning 1950 documentary film chronicling his adventures, and the 2012 dramatized feature film nominated for the Academy Award for Best Foreign Language Film. The raft was named Kon-Tiki after the Inca god Viracocha, for whom 'Kon-Tiki' was said to be an old name.

The Kon-Tiki expedition was a 1947 journey by raft across the Pacific Ocean from South America to the Polynesian islands, led by Norwegian explorer and writer Thor Heyerdahl.

The Kon-Tiki raft at the Kon-Tiki Museum, Oslo

Kon tiki across the pacific by raft