The pike square (German: Gevierthaufen, lit. 'square crowd', or Gewalthaufen lit. 'crowd of force') was a military tactical formation in which 10 rows of men in 10 columns wielding pikes developed by the Swiss Confederacy during the 14th century for use by its infantry.
The pike square was used to devastating effect at the Battle of Nancy against Charles the Bold of Burgundy in 1477, when the Swiss defeated a smaller but more powerful armored cavalry force. The battle is generally seen as one of the turning points that established the infantry as the primary fighting arm in European warfare from the 16th century onwards.
The Burgundian compagnie d'ordonnance was a formidable combined arms force relying on close cooperation between heavily armored knights, dismounted men-at-arms, a variety of ranged troops including archers and crossbowmen, and an early form of field artillery. It was one of the most feared and most effective ground forces in 15th-century Europe, fresh from its victory over the French in the dynastic conflicts that followed the end of the Hundred Years' War. In response to the Burgundian threat the Swiss developed a tactic that could be used by mobile, lightly armored soldiers carrying only a long, steel-tipped pike for defence. However, the tactic depended on well trained and drilled troops who could move in unison while in close formation. While the use of pikes to fend off cavalry was common throughout the Middle Ages, such barricades were usually fixed in position. The Swiss pikemen were to bring a change of paradigm by reintroducing the offensive element into pike warfare.
A pike square generally consisted of about 100 men in a 10×10 formation. While on the move, the pike would be carried vertically. However, the troops were drilled to be able to point their pikes in any direction while stationary, with the men in the front of the formation kneeling to allow the men in the center or back to point their pikes over their heads. While stationary, the staff of each pike could be butted against the ground, giving it resistance against attack.