Many physical, sword and gun fights are depicted.
In series 1 there is very little blood (in the first episode, the only blood scene is after the wound, i.e. blood pooling on the grass around a dead body, bloodstain on clothes around a musketball wound). There are swordfights and shootings, but actual impacts are cut around, obscured or offscreen.
The show becomes more violent in the second series, frequently showing people stabbed and shot. There is more physical fighting, with some characters having their necks broken. In one scene a man is stabbed out of shot but his body is then dragged across the floor leaving a trail of blood.