What is "pre-celtic"

The term pre-Celtic refers to the period in the prehistory of Central and Western Europe postdating the emergence of the Proto-Celtic language and cultures and predating the expansion of the Celts or their culture in Iron Age Europe and Anatolia (9th to 6th centuries BC). The area involved is that of the maximum extent of the Celtic languages in about the mid 1st century BC. The extent to which Celtic language, culture and genetics coincided and interacted during this period remains very uncertain and controversial.