The exposition of "The Interlopers" by Saki is full of important information and sets the tone for the story. It is a stormy night in a forest, and that can never mean anything good for at least some of the characters in a story. Two pieces of information are revealed which are quite important to the rest of the plot.
First, the narrator establishes the fact that the two main characters in the story are enemies. They are not just simple enemies, but they are the third generation of a family feud over a "worthless strip of land." The courts have ruled on the matter, but there is still contention over ownership between the two families. Now it is a personal feud.
The feud might, perhaps, have died down or been compromised if the personal ill-will of the two men had not stood in the way; as boys they had thirsted for one another's blood, as men each prayed that misfortune might fall on the other....
Second, both of those men, Georg and Ulrich, are in the forest tonight, and they both are interested in human prey rather than animals. They are here to hunt and kill one another. Trouble is ahead.