The Viking Quest Game is from the BBC.  Players take on the role of a Viking and get to do many things, including looting a monastery.  It’s probably most accessible to High Intermediate and Advanced English Language Learners.

I’ve placed it on my World History page in the middle of The Middle Ages section.

One of things I, and my students, like about my website is that in just about every section they can find links that are appropriate to their English level.