The 14th and the beginning of 15th centuries were characterized by fast development of arms, tactics and strategy as well. Knighthood of the Kingdom of Poland strengthened for good, and in the battlefield developed and dominated maneuverability, with full scale outflanking, surrounding, unconventional uses of cavalry and infantry units to surprise the enemy.In those days commanders stayed away from the fight, observing battle from a carefully selected place (mostly at the top of the hill), from where they had a wide view over the surroundings. All detachments were led by known, experienced knights named voyvodes.
Polish army of that period consisted - as before - of knights, burghers, and peasants, with obvious division of labor and specialization: cavalry, infantry, and fortified cities defenders. The knight, along with his lance belonged to his own chorągiew (or rota) of land, clan, or mercenary, and the best warriors were called to lead the chorągiews of the army. Szlachta of moderate means, able to arm and support the lance, enlisted to a chorągiew of a particular land, where knights had their estates. Poorer knights enlisted to the chorągiews created and maintained by magnates, or to a few mercenary royal chorągiews created under king's order by a particular, rich and famous commandander. Infantry was made up of peasants (one of five men of royal villages: four remaining in the village had to equip and arm the fifth). Burghers had to defend their cities, and different guilds were responsible for particular part of the walls' defense. They, as much richer than peasants, were able to get much better armours and weapons: light helmets, mail, or mail-plate armours; in addition they were taught how to fight, for which purpose the shot brotherhoods were created.
The weapon of the knight changed a little: swords were longer, some with long cruciform hilts with grips over 15 cm in length (providing room for two hands), straight double-edged blades often over 90 cm in length, and weigh typically between 1.2 and 1.4 kg (so called longswords or bastards). On the contrary armour transformed significantly. Mail was gradually enriched with iron plates, which covered the most of endangered parts of the body, and in the beginning of 15th century was replaced with full plate armour. Worth to know that the armour was covered with outer garment of tunic form, open at the sides and so usually belted, usually emblazoned with coats of arms, known as tabard. Uncomfortable great helms went out of use, replaced with first visored bascinets, typically fitted with an aventail and hinged visor.
The crossbows of infantry became heavier, and more dangerous for the knights, and the ordinary shield of the past was replaced with the pavise; a high, rectangle shield, from behind which a foot soldier could safely shoot at the enemy. The very last inventions of the 15th century were black powder and cannon. The latter was for the first time used in Poland after the death of king Louis I of Hungary, when followers of one of candidates to the throne besieged their opponents in the castle of Pyzdry in 1383. Bombards of that times, which shot stone projectiles, were quite good against fortifications, but almost useless on the battlefield.