Riding horses into battle is really tricky. For cavellery horses, basically you have to keep riding towards a crowd with the horse. During training, the crowd is your accomplice, and as soon as the horse approaches, everyone in the path of the horse steps out of the way. You do that over and over, until the horse is confident that the humans will always step out of the way. Once the horse is confident enough, it will be willing to go faster. You keep training the horse, until it can truly charge quickly. Then finally, if there is a real battle, you can use all uour trained horses, to charge once. Any horse that gets even slightly hurt during the charge, will likely never trust you again. Because humans fucking suck, and can’t be trusted.