As far as the men dying early, that's in comparison to the women who survived into their 30s and 40s, but warfare wasn't all that big a deal in peasant societies.
War was for gentlemen ~ the wealthy and powerful.
They were, of course, generally the guys who started it.
But, as an example, during most of the Middle Ages the primary way to fight a war was to "ravage" your opponent's territory. This meant burning his farms and killing his peasants. This was really hard on the peasants. Meanwhile the lord hung out in his castle.
Even when this was not a specific war policy, undisciplined armies moving through your village was a disaster.
During the 100 Years War, Normandy lost 3/4 of its population.
In the early modern period, the 30 Years War reduced the population of Germany by somewhere around 50%.
We routinely consider modern wars much more destructive than those of the past, but this is quite untrue on a percentage, as opposed to absolute basis, which is the proper way to compare. Poland, the country with the highest loss of life during the war, lost about 16%. While horrific, this was rather minor in comparison to routine impacts of many earlier wars there and elsewhere.
In WWII Germany lost 8% to 10%. Japan 4% to 5%. USSR 13.5%. USA 0.32%.
http://en.wikipedia.org/wiki/World_War_II_casualties