For those that believe in science.

"Humans and their close Neanderthal relatives began diverging from a common ancestor about 700,000 years ago, and the two groups split permanently some 300,000 years later, according to two of the most detailed analyses of Neanderthal DNA to date. Using different techniques, two teams of scientists separately sequenced large chunks of DNA extracted from the femur of a 38,000-year-old Neanderthal specimen found in a cave [image] 26 years ago in Croatia. One team sequenced more than one million base pairs and the other 65,000 pairs of the genome."

http://www.livescience.com/humanbiology/061115_neanderthal_dna.html