Throughout feudal history it seems like there are a lot of conflicts where feudal figures go to war, lots of peasants die, and sometimes more or less the feudal status quo remains, maybe even no change in feudal leadership / goal's accomplished or etc.
I'm sure this is influenced by my modern sensibilities but this seems like a pretty raw deal for the peasants to the extent that I wonder how you motivate peasants to go kill other neighboring peasants only to return home to ... still be a peasants.
Were they rewarded financially for this risk? Provided more land to farm / displaced other peasants if they were victorious?
Was it often simply a case of being required by your local lord and fear of punishment if you didn't comply?
I understand this is a topic that asks about the mindset of people whose mindset we don't know much about (peasants) and the time frame might be wide ranging here, simply using 'feudal' (seems to be a vague term) but I'd be open to any answers or theories on this topic from any time frame. It would be understandable that different situations and time periods might involve different answers.
Well, that depends on just exactly what you mean by 'peasant', as it is entirely possible that what you're envisioning by the word may not match what happened then. More can always be said on the matter, of course, so any further insight is welcome from anyone who'd like to post.
For the meantime, u/Rittermeister has three posts that examine participation in combat and why they'd fight. If you have further questions, we're always happy to answer follow-ups, and it's also likely that they may already have been answered, in which case I can dig up more posts for you.