Europe is without a doubt the best place to detect if you're looking for anything from the WWI, WWII, the industrial age, medieval times and all the way back to the Roman Empire. I had the luxury of detecting in Germany for 3 years and found silver coins which date to the 1200s. Heck the first old coin I found was a 1/2 Stuber from 1785. At first I could not believe I had found a coin from the 18th century. My mind had a hard time registering that I had just dug something out of the ground that old. It'll put a smile on your face for a few weeks for sure!
Hopefully you get the chance to go back for more detecting. Good luck.