Well, a lot of people like to be condescending about the tactics used in the Medieval Era, but the simple fact is that they were good enough and for the most part they worked. Also remember that it's pretty easy to feel condescending about real historical tactics when you are playing a GAME which allows you alot of flexibilities in tactics and manuever that would never have been possible in real life.

But, at any rate, a tactic used in many battles in the dark ages was the idea of a shield wall, that the main line of infantry, armed with throwing spears and swords or axes, would form a formidable wall of shields which would be difficult for the enemy to break. Archers, usually deployed out in front or in the first couple of ranks of this formation, would shoot arrows from a distance, and if the enemy shot back, they would pick up those arrows and keep using them, so that an archery duel could last for quite a while.

A good example of this would be the Battle of Hastings. Here we can see that the Shield Wall was effective in holding the Normans back and in stopping their heavy cavalry, but that with time, attrition due to archery, repeated charges, and the elimination of a foolhardy contingent of Saxons who pursued fleeing Norman infantry down the hill, gaps opened up which the Norman cavalry was able exploit.

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Later on a common tactic was to recruit masses of unreliable peasants as infantry, and rely on a devastating Heavy Cavalry charge to win the battle. The English often relied on a devastating salvo of archery to be the decisive factor in battle.

Anyway, there's alot more to it, but that's a starter.

DA