Reddit reviews Myths and Symbols in Pagan Europe: Early Scandinavian and Celtic Religions
We found 3 Reddit comments about Myths and Symbols in Pagan Europe: Early Scandinavian and Celtic Religions. Here are the top ones, ranked by their Reddit score.
Used Book in Good Condition
A Celtic Miscellany: Selected and Translated by Kenneth Hurlstone Jackson to get an idea of the variety within 'Celticism' and to get a feel of the myths and tales.
The Celts: Bronze Age to New Age by Haywood. A bit of a general book about the Celts.
Myths and Symbols in Pagan Europe: Early Scandinavian and Celtic Religions by H R Ellis Davidson. A more scholarly work placing the Celts in the larger context of Northern European peoples.
Of course there's plenty more.
I'll have to check that one out myself.
A lot broader (and a little pricier) is "A History of Pagan Europe" by Nigel Pennick and Prudence Jones, but you can preview a decent amount on Amazon. If you go to Table of Contents and click on Chapter 5, that has some basics about the Celts (including the Helvetii) and touches on some similarities and differences between Celtic and Germanic traditions: https://www.amazon.com/History-Pagan-Europe-Prudence-Jones/dp/0415158044
"Myths and Symbols in Pagan Europe" might be worth it, too; if you buy a used paperback it's not too expensive. If I remember correctly, it's a bit more dense, but both of these books are fairly academic: https://www.amazon.com/Myths-Symbols-Pagan-Europe-Scandinavian/dp/0815624417
I've only read bits and pieces of both, so I'm not comfortable recommending them, exactly, but they might have some of the info you're looking for.
This book is written in timeline and contrasts between belief systems.
It's dry, but is well researched and insightful to me.