Any intermediate level books about Vikings or Greeks?

I hope this post finds the community well.

I am looking for book recommendations as a gift for someone who is about A2-B1 level in English.

They love both the mythology and history of Vikings and the Greeks. But the catch is they aren’t too good at English and are willing to use the book to improve.

(And while at it, you could suggest something of more advanced level for myself lol.)

Thank you in advance for your help!