The so-called Three Age System was developed by the Danish curator of the National Museum of Denmark C.J. Thomsen, at the instigation of his predecessor Rasmus Nyerup, and to resolve display issues.
During the 19th century, many many many educated, wealthy young European men scattered around the globe, collecting artifacts from all corners, whether purchased, stolen, or dug out of archaeological sites. This chaos was then brought home to museums where the curators were faced with displaying them in some manner. Thomsen sorted the museum's objects by the material culture, resulting in separate rooms for Stone Age, Bronze (originally Brass, oddly enough) Age, and Iron Age. He suggested that the order was probably chronological; a fact established later by archaeologist J.A.A. Worsaae.
Flaws of the Three Age System
The system isn't perfect; as is quite clear by anybody who has done reading of the literature, the technological change from stone to bronze to iron doesn't coincide with social changes except in the broadest of senses. Still, not bad for 150 years ago, when Thomsen had no dates, no context, and no clue about the cultures for some of the objects in his museum.
More Information
Read more about the creation of the Three Age System in the History of Archaeology: The Biologist, the Geologist, and the Museum Director.
This glossary entry is part of the Guide to Dating Techniques in Archaeology and the Dictionary of Archaeology.
