Why Do Most Spiral Staircases Ascend In a Clockwise Direction and How Did They Originate?

Spiral staircases originated as a defense mechanism in medieval castles because all knights were right-handed.

Southpaws were considered under the Devil’s influence and were automatically disqualified for knighthood.

While ascending a clockwise spiral staircase backwards with a sword in his right hand, the defending knight could freely swing his sword arm, while the attacker was neutralized by the wall blocking his own right arm.