Disclaimer - I was an English major and history nerd - my tastes are NOT what most would consider "normal". Take these recommendations with a grain (or dozen) of salt.
Depends what you're looking for. For straight up history stuff, I'd recommend anything written by Frances and Joseph Gies. I have 8 of their books (and am currently reading #6), but I believe they've written about 20. They focus on a specific topic per book, from "Life In A Medieval _____" (either, City, Village, or Castle), to their study of the knight through history, on to marriage and family and my current read, women in the Middle Ages. They take what could be an incredibly dull subject and synthesize countless sources into a narrative of sorts, tracing a certain location or type of person through the entire time period of the Middle Ages, discussing the changing and evolving roles of the people and locations as well. They manage to make it eminently readable, which I find to be no small task.
As for Vikings, I've just been reading all sorts of sagas. From the Icelandic sagas, to various heroic sagas and the Saga of the Jomsvikings, they're entertaining - if you like this sort of stuff. It interests me how many times the main character of one saga is mentioned as a hanger-on of the character of another saga, and they are often self-referential. As with many large topics, the more you read, the more you notice. I think my favorite has been
"Sagas of the Icelanders" which is an anthology of sorts, so there's likely something you'd enjoy.
Hope you enjoy some of these!
