WWI was a complicated and drawn-out war. It was the eruption of many different inter- and intra-national conflicts which drew on and on. These conflicts led to devastating losses for all of the parties involved. Many countries and regions formed alliances with others and fought on multiple fronts; the war lasted for just over four years and involved a series of crises all around the world. The opening passage of The Interlopers goes into detail about ongoing disputes about a very small piece of land; this is similar to the political backdrop of WWI.
One of the enduring traumas of WWI was trench warfare. The Western Front was one of the main battle areas and the lines hardly moved for two years despite being the site of millions of deaths. The men fighting against each other in the trenches were so close to their enemies but had no control over the battles; this is similar to the conversation between Georg and Ulrich while they are pinned under the trees. The two men eventually call a truce with each other, giving in to their humanity. They put aside their petty quarrels about land—their old feuds—and decide to form peace and show it to the villagers. Georg and Ulrich imagine the bright future that they have together, talking about feasting and how, if they are allied, there will be “none other to interfere, no interlopers from outside.” This positivity and hope for the future is dashed when they see that it is not their men who come for them, but wolves.
The wolves, in this case, can be seen as a metaphor for the technology of war. The technology used in WWI was unprecedented: poison gas and tanks in particular cannot be reasoned with like another human in close combat. Just as there is no way to negotiate with a canister of poison gas tossed into a trench, there is no way to negotiate with wolves.