The book opens with a first person narrator describing the events of "that year," with the specific year unspecified as of yet. We know almost nothing about the nameless, ageless, genderless narrator--besides for the four uses of the word "we," this section reads as third person narration. Third person narration, that is, describing equally covert soldiers of an unidentified army, fighting a mysterious war.
So, point is, at this stage we know almost nothing about any of the characters or the narrative of this particular plot. That is because, I posit, the first chapter isn't about anything or anyone in particular. These first two pages are about war and its effects.
Consider the following:
Troops went by the house and down the road and the dust they raised powdered the leaves of the trees.War affects nature, changing even the leaves of the trees.
There was fighting in the mountains and at night we could see the flashes from the artillery.War affects daily cycles, illuminating the night.
Sometimes in the dark we heard the troops marching under the window and guns going past pulled by motor-tractors. There was much traffic at night and many mules on the roads with boxes of ammunition on each side of their pack-saddles and gray motor trucks that carried men, and other trucks with loads covered with canvas that moved slower in the traffic.War affects human behavior, increasing traffic when there normally is none.
The way Hemingway sets the stage for what became known as perhaps the best American novel about World War 1 (at least according to the book's back cover) is exceedingly cool. I look forward to the next 328 pages.