An archaeological culture is a recurring assemblage of artifacts from a specific time and place that may constitute the material culture remains of a particular past human society. The connection between the artifacts is based on archaeologists' understanding and interpretation and does not necessarily relate to real groups of humans in the past. The concept of archaeological culture is fundamental to culture-historical archaeology.
Different cultural groups have material culture items that differ both functionally and aesthetically due to varying cultural and social practices. This notion is observably true on the broadest scales. For example, the equipment associated with the brewing of tea varies greatly across the world. Social relations to material culture often include notions of identity and status.
Advocates of culture-historical archaeology use the notion to argue that sets of material culture can be used to trace ancient groups of people that were either self-identifying societies or ethnic groups. The classic definition of this idea comes from Gordon Childe:
We find certain types of remains -- pots, implements, ornaments, burial rites and house forms -- constantly recurring together. Such a complex of associated traits we shall call a "cultural group" or just a "culture". We assume that such a complex is the material expression of what today we would call "a people".
The concept of an archaeological culture was crucial to linking the typological analysis of archaeological evidence to mechanisms that attempted to explain why they change through time. The key explanations favoured by culture-historians were the diffusion of forms from one group to another or the migration of the peoples themselves. A simplistic example of the process might be that if one pottery-type had handles very similar to those of a neighbouring type but decoration similar to a different neighbour, the idea for the two features might have diffused from the neighbours. Conversely, if one pottery-type suddenly replaces a great diversity of pottery types in an entire region, that might be interpreted as a new group migrating in with this new style.