SciFi and Fantasy Book Club discussion

I've been searching for years to try and find this book I read as a teenager. All I remember is it starts out with some archeologists finding a mummified female body in a tree. She was Celtic and sacrificed for some reason. There was a love story with her and a young man who also died. They weren't allowed to be together. It was so long ago but very moving when I read it and would desperately love to read it again someday. Thanks

the only one that comes to mind is The red Man by Anna Reith hope this helps