I don't have the answer, and I'm eager to see somebody try to answer this, but when it comes to written historical records there are two main problems with trying to answer your question...

• Most ancient histories are written by the upper class, for the upper class, and there is little reference to the everyday life of common folk.

• The people of pre-roman Gaul and Germania were illiterate, so no writings are available anyway. Vague descriptions of meeting these people are given by early Greeks and Julius Caesar, but they are short descriptions.

Archeology tells much more about those people than any available first hand written records.