The primary weapon of the Medieval knight was the lance. Swords were worn by most knights, and like the lance had symbolic significance. 
On a more practical level, a sword could be worn on the belt or mounted on the saddle and rapidly drawn, making them useful back-up weapons. For many knights the sword was not their first choice of melee weapon, however. Widespread use of armour often required something harder hitting. One such weapon was the war-hammer. Long handled hammers were used for foot combat both on the battlefield and in the tournament. The hammer was also well suited to mounted warfare, with the “horseman’s hammer” constituting a whole sub-class of weapon. Since it concentrates its force a hammer hits harder than a sword but can use a lighter head than an axe or mace. This allows the use of a longer haft, giving the horseman more reach. Many hammers were equipped with a backspike, beak or pick, increasing versatility. A blow with the point could penetrate armour, but did have the risk of the pick becoming stuck. A blow with the hammer poll had less risk of sticking but might still buckle the armour and damage the body beneath, or just knock the enemy from his saddle. Doubtless the pick/ backspike could be used to hook and pull an enemy on occasion.
On a more practical level, a sword could be worn on the belt or mounted on the saddle and rapidly drawn, making them useful back-up weapons. For many knights the sword was not their first choice of melee weapon, however. Widespread use of armour often required something harder hitting. One such weapon was the war-hammer. Long handled hammers were used for foot combat both on the battlefield and in the tournament. The hammer was also well suited to mounted warfare, with the “horseman’s hammer” constituting a whole sub-class of weapon. Since it concentrates its force a hammer hits harder than a sword but can use a lighter head than an axe or mace. This allows the use of a longer haft, giving the horseman more reach. Many hammers were equipped with a backspike, beak or pick, increasing versatility. A blow with the point could penetrate armour, but did have the risk of the pick becoming stuck. A blow with the hammer poll had less risk of sticking but might still buckle the armour and damage the body beneath, or just knock the enemy from his saddle. Doubtless the pick/ backspike could be used to hook and pull an enemy on occasion.According to arms historian Cameron Stone the war-hammer has been used by all nations that used armour, with the exception of the Japanese. He also observes it was a more popular weapon in the Western World, where armour tended to be heavier, than in the East. The American Indians also found the hammer to be a useful cavalry weapon. Since they rarely encountered plate armour their version mounted a rugby ball shaped stone at the top of a wooden shaft. While short-handled versions of this weapon exist handles of up to 30" long seem to indicate this was the equivalent of a horseman’s hammer
The Victorian cavalryman suffered a long succession of poor quality swords and I was interested to read one after-skirmish report where the observer commented that the troopers would have done more damage if they had been armed with stout sticks. Perhaps if someone had taken this to its logical conclusion the horseman’s hammer would have seen a renaissance!
Interestingly, while searching for images for this blog I came across this picture of a Hungarian Hussar that seems to indicate hammers were used much later than I suspected. Since most armies copied the Hungarian Hussars it is surprising the hammer did not see wider use in later centuries.
