Yes when they went to war over an arguement the core of which they had already been resolved but communication of that development was slow, it then had a rather famous battle in 1815 which started after the war had ended but the paperwork was in snailmail, you could add that a month after that they had another battle as they still hadn't got the news the war was over. If you want to go to the full extremes then Warrington in the USS Peacock was still playing silly buggers trying to make a few dollars out of the war 6 months later, even when people were telling him the war was long over he still was killing people "in the war"