were influenced by Henry IV's ideas, whether directly or through Dutch mediation – especially by the agency of Swedish officers who served in the Low Countries (Eighty Years' War), such as Jacob De la Gardie. Infantry countertactics Against light cavalry with bows and javelins It was impossible for infantry to engage light cavalry with bows and javelins in close combat on ground that did not seriously hinder cavalry movement. The only resort for engagement were missile weapons in ranged combat. In this case both cavalry and infantry fought only in a missile exchange. While the infantry can be considered static in comparison to the cavalry, their own protection, the damage their missiles would cause and the hit rate were important. For example, in the prelude to the Battle of Mohi, crossbowmen protected by pavises sniped at the Mongol light cavalry, resulting in a tactical defeat of this Mongol unit, although the Mongols did go on to win the overall battle. The defence of such ranged combat units was important, for cavalry could always switch roles and engage the ranged combat infantry (often lightly armored skirmishers) in close combat. Against heavy cavalry with lances The longbow and the crossbow were able to counter the dominance of mounted knights on the battlefield. Although knights of the Middle Ages often fought on foot or at least avoided futile frontal attacks, it happened several times that knightly armies led charges in obeyance to their warrior ideal only to meet with disaster. At Crécy (1346) and Poitiers (1356), the French knights suffered heavy casualties against the Welsh and English longbowmen. The ability to keep several arrows in the air at any given time was an important advantage of the medieval archer. Thus, while a cavalry charge followed a strict pattern of acceleration (400 metres in 2 minutes, gallop at the last 150 metres) from a distance beyond effective missile range, once they came within range they could be met with a hail of arrows that could severely injure both horse and rider alike. However, unsupported light infantry and archers would not be able to cause enough casualties to a cavalry force, if it were charging across suitable terrain, to tip the odds in their favour in the following melee. Thus, it was always advisable for missile troops to fight on terrain disadvantageous to cavalry charges, and with supporting heavy infantry close by. The long spears