Like all good stories, there are several important themes. Let me delve into two of them.
First, the most obvious feature of the story is the feud that exists between the two families. Ulrich Gradwitz and Georg Znaeym hate each other, even though they do not know much of each other. Here is a quote on their hatred.
...if there was a man in the world whom [Ulrich] detested and wished ill to, it was Georg Znaeym, the inheritor of the quarrel and the tireless game snatcher and raider of the disputed border forest.
The foolishness of this hatred is obvious, because they inherited it. So, they hate blindly. Why perpetuate hatred? Why inherit a feud? Hence, the theme of blind hate is present. That their hatred is foolish is confirmed as they become friends as they spend time together. In fact, they seek to outdo one another in kindness by the end.
Second, there is also a theme of who is the real interloper. The men accuse each other of trespassing, but it may be that the men are the trespassers. Can they own the tract of land? At the end of the story when the wolves come, it is implied that they are foolish to think that they can own the land. Nature cannot be owned or tamed.
As for events, the three main events are: the storm that takes place in the beginning of the story that fells a tree on the two men; the reconciliation that takes place between the two men; and the impending death of the men as wolves come.