what do we think it would be like for the gauls (of that village we all know so well) to hear that julius caesar got killed by his own inner circle? i mean sure, as a whole they probably hold a banquet- any excuse is a good excuse, and the death of your enemy is a pretty good one as is.
a few of them, though, have called truces with him. recognized each other's merit as warriors and leaders and such. and yeah, its still a good thing for them. its not like theyve ever gone out of their way to try to kill him- they really only want to keep their hometown safe- but if he'd directly gotten in the way of that, whatever, right? and yet to find out he suddenly died, and not even by gaulish hands? that would be a surprise, at least.
obelix would probably be mostly disappointed they weren't there for a big brawl like that, but he is a softie, so he might be upset by it as well. asterix, though... i don't know. he probably interacted the most with the man, cutting deals and talking to him like an old friend, even just to get under his skin by being disrespectful. he's been the biggest pain in jules' side, and had a blast doing it. and as the villages only warrior by title, im sure he saw this coming eventually. but i think he saw himself doing it, when the time came. personally seeing the job done, and having that closure. not waking up one morning to the calls of a messenger, and having the world shift.
i dont know how he'd feel. but i think he'd be the closest to grief.