Book Log 2020 #57: The Eight by Katherine Neville
A computer programmer in the 1970s and a novice nun in revolutionary France both get swept up in the hunt for a chess set that used to belong to Charlemange and is said to give great power to whoever possesses it. In the older timeline, the goal is to disperse the set so no one can use it for their own ends, while in the modern timeline the goal is to find the set to keep it out of the hands of those who are seeking it, also to use it for their own ends.
This book was apparently quite a sensation when it was released in 1988, but I had a hard time getting through it. The book clocks in at over 600 pages, and often felt longer. I didn't put too much thought into the idea of a magic chess set, which probably helped. Suffice it to say I'm not hunting down the sequel.