A really good first attempt at a novel, way better than my first attempt by a long shot.
Overall, there's not really any specifics I can give for improvements, so please forgive me if I'm rambling and vague.
Raven is right, why is the bell so far away? You made it sound like the bell was the farthest reaches of the frontier, which makes no sense, because it should be closer to them, and closer to the Holy Empire(I think that's what it is..) so the knights can respond quicker. Maybe you have a purpose for that though.
Until he discovered Marshall's death, I wasn't feeling the love of Jarl for his family enough. You kind've
tell us that he's important, and couldn't live without him; which is fine, because he probably would be thinking along those lines at the time, but I wanted more body language to show me how he felt. Up until he discovers his death, then it's portrayed much more passionately.
By the gods I am going to put an arrow in that thing if I have to do it from point blank range.
I'm not really an expert, but would the term "point blank range" be in use in this time period? It jarred me out of the story a bit.
And why were the wildmen and the Hound waiting at the house. They had been there for well over an hour after killing his family, were they just waiting for him? Because that seems out of character of dumb and unsophisticated wildmen, when they couldn't even have been sure of a male who lived there. And if they were waiting there, they could have taken him out before he got inside the house. That part doesn't seem to be entirely realistic,but I can forgive that, because all authors do that to some extent, or maybe it's more complicated and we simply havn't read enough to understand it all. Either way, good job overall.
But this chapter is a good hook, well written, good characterization and some worldbuilding without giving a massive infodump. And the sneak peak of the 2nd chapter looked promising. I will eagerly await your next submission!