1. Is this something that can be survived without modern medical treatment? While they do have healing magic, there's also the problem of pre-modern people not really knowing the importance of the brain, so I'm not sure it's realistic for the healers to focus on that. Can you conceivably have a case of skull fracture without severe bleeding or swelling in the brain?
2. The injury happens while the character is fighting another. Can a large, strong person swinging a heavy object conceivably fracture the skull of an average-sized person? The exact weight of the "heavy object" is negotiable -- it's a small statue.
I've been reading about skull fractures and tried searching to find the force required, and then I tried messing around with force calculators to see if the offending character really could get up the force required. Unfortunately I'm not well-grounded in physics, so I just wound up confused. I understand that the skull of a living human is a very strong thing that does not break easily... and yet I hear about stories where people suffer skull fractures as a result of physical assault.
I know that there's no set outcome for any situation that meets this description. Mostly I need to know if it's realistic or not. Again, the exact weight of the statue can vary (though it can't be so heavy that a strong man can't lift it and swing it). The sight of fracture can also vary if the top of the skull is too strong. And finally, since this is mostly to add juicy drama, I can scrap the whole fracture thing and just have him get an extremely painful concussion... so if the whole situation seems ridiculous, please say so. ;)
ETA: This community is awesomely helpful. Thank you to everyone who responded!