Ride Roughshod Over Someone

In the modern world, riding roughshod means disregarding someone’s feelings or opinion. Basically, run them over. On the medieval battlefields though it had a different meaning.

The goal of the mounted knight was to cause as much damage on the battlefield as possible. They really kind of were the forerunners to tanks. Not content to let the damage be done by the lance, spear, sword or the thousand pound horse slicing through an enemy other means of violence neede found. As such the knights would have the blacksmiths “roughshod” the horse by leaving every second nail sticking out of the show. So not only would they run you over, but they would tear you up in the process.