What was the longest or bloodiest war you ever fought in Civ5? In one game, I was Askia and I fought a long and bloody war with the Aztecs. I attacked them a 1000 years prior, but they drove me out. I decided my conquering spree was over and focused on science and commerce. The Aztecs held a grudge for a millennium because I razed a city in our previous war. In the 19th Century, he DOW'd me once I withdrew troops from the border. Most of the fighting took place along the border and the war lasted almost a century. Even though Monty had the world's most powerful military, I managed to hold out long enough for him to offer an unconditional truce. It was technically a stalemate, as there were neither side gained nor lost any territory. There was also very little damage to infrastructure. The only real devastation from the war was the number of soldiers killed on both sides and we both threw cannon fodder at each other for the entire duration of the war. I guess I technically won as Monty couldn't take any of my cities and I a quickly caught up with him in military technology and he offered a truth once my units barely made it pass his border. After that, we actually became friends. I guess I won his respect by not being a pushover.