In the Museum of Anthropology in Lima Peru, there is a large room which contains quite possibly the world’s largest collection of ancient human skulls, all presumably found in Peru itself. The fact that this country has thousands of years of cultural history, and thus graves, makes such a collection possible.
Many it seems are from the Paracas area, south of the capital Lima. The Paracas culture are known around the world for their elaborate textiles, and the fact the the noble classes had elongated skulls. What is curious, or indeed strange is that the elongated skull phenomenon is not being actively studied by academics.
As the Paracas died out as a distinct culture about 2000 years ago, partially because of climate change, but mainly exacerbated by the encroachment of what became the Nazca people, we do not know exactly why they performed cranial deformation. Or, in fact, where these people came from in the first place.
However, we presume that the elite classes, to whom this process was done, wanted to physically stand out from the commoners, and thus altered the shape of their children soon after birth. And, perhaps their ancestors actually looked like this.
Shapes other than the “cone heads” above were achieved by the Paracas and other ancient people. The reason for the different shapes may have been to distinguish the different forms of status, such as religious and ruler classes.