The Egtved Girl
In 1921, the well-preserved remains of a Bronze Age girl were discovered in Denmark. Dating back to 1370 BC, it has recently been found that she was not actually Danish but most probably from Southern Germany.
The body was found dressed and decorated, covered by a blanket and cowhide, and it was really the textiles that preserved so well and caused a sensation when the body was discovered in a coffin. But now isotope dating has revealed that she and her coverings actually came from elsewhere and travelled to Denmark in the last two years of her life. It is a fascinating revelation which you can read here. Immigration is nothing new!
(Photo credits: http://en.wikipedia.org/wiki/File:Egtved_Girl.gif)