Early Firearm Tactics: Pike and Arquebus
The arquebusiers, belonging to the same unit as the pikemen, did not operate completely independently…. In the absence of obstructed terrain, the square of pikemen provided the only place of safety where the light infantry might take refuge from the enemy’s heavy cavalry. They could take a position on the flank of or behind the square, or, should the cavalry attack in flank or rear, many could find safety in the front ranks where the wall of pikes would protect them. In turn, the arquebusiers’ fire could support the pikemen’s defense, and the masses of the enemy’s heavy infantry or the horses and men of the attacking heavy cavalry would provide fine targets for arquebus balls. The Spaniards gradually increased the proportion of arquebusiers to pikemen until, by the end of the 16th century [C.E.], their regiments approached equal numbers of light and heavy infantry.