MEDIEVAL WAR : FROM FEUDALISM TO GUNPOWDER. As soon as you get advanced to Middle Ages a new problem appears: adapting to the new methods of warfare, that is a bit different from those of Ancient Era. A new, superior defensive unit becoms available, pikeman. It's defensive strength makes horsemen, knight and even cavalry to leave the battlefield after almost each battle. There are few solutions on bringing them down. Even a 1hp pikemen can kill a full-healthed knight. So, cavalry cannot solve this problem even in conjunction with catapults. Even a Longbowman, with its infernal attack strength can lose a combat against pikeman. The best unit suited for taking out the pikemen is a swordsman. Infantry dramatically changes throughout the Middle Ages. From spearmen through pikemen to musketmen. From archer to longbowman. The task of attacking infantry is to destroy defensive spearmen, pikemen and hoplites. But attacking infantry has a puny defensive factor. They are not to be left fortified to guard a city. Attacking infantry is a kind of assault troops (like marines or paratroopers). Knight is a mounted unit with good attack and defensive capabilities. They are good for exploring, scouting, spying and so on. Also, they can retire from combat (to be repaired at your nearby town). Knights should be used to cover your longbowmen and swordsmen from attacks of an enemy assault infantry. What about catapults? This kind of weapon is taken from ancient times, but it's still powerful in Middle Ages. If the target location is surrounded by forests or mountains, you are to task your workers there to build a road. A catapult has a bombard capability. So, it can be used to perform a revolution in your enemy's empire. Encircle an enemy city, pillage out all terrain improvements yo cut the city out from luxuries and other resources and to minimize trade (that lower the quantity of "happy faces" in this city, then bombard the city. If the Courthouse is destroyed, corruption just rushes in this city (so there is 0 luxury income), and if Cathedral, Colosseum and Temple are destroyed, it causes disorder in the city. When you see the city smoking, set out for the next target. A disordered city can cause overthrowing the government and enemy's production, trade and science goes to hell for three turns. I consider this kind of forcing the government a part of medieval tactics because Cathedrals, Colosseums, Marketplaces and Courthouses are used mainly during Middle Ages. One of the most important factors is civilization. There are 3 civs in the original Civ3 game that have medieval UU -- India, China and Japan (all of them are Far Eastern). Those UUs are built instead of Knights and enabled by Chivalry. I think, the best way to build up a strong military and to win a medieval war is choosing Chinese, with their attributes and very mobile Chinese Riders. Indians re not so powerful, but they have War Elephant, a unit that demands no resources to build it and as strong as Knight. Japanese civilization is a "golden mean" between Chinese and Indians with Chinese militarism and Indian religiousness, and their unit, Samurai, requires nor two neither none resources, needing only iron to be built. You have to use "combined arms" in early medieval wars. For example, to take an unwalled town, 2 knights, 2 pikemen, 2 swordsmen, 2 catapults, 2 longbowmen are needed. If all these units survive, half of them are left at the city, others attack another town. If you attack a city or a walled town, then the forces should be doubled. If you want to attack their capital, you are to have 8 units of each type to ensure a firm effect. You have to prepare for the war if you come across an opponent. One of the most meaningful parts of preparation is investigating your enemies cities before the war using your embassies. Trade with other players (with luxuries and techs) to maintain friendly relations with them (it will be needed when you declare war to form military alliances against your hated rival).