Obviously, in order to build a castle one must have land on which to place it. In the typical AD&D® game, there are many ways to obtain land. Some are above board and heroic, others are not. The choice of techniques possible in a campaign is left up to the DM, with the exact method employed left in the hands of the players.
One of the most well known means of coming into possession of an estate is through the attainment of a Royal Charter. A charter is an official document from a king or emperor which gives legal permission to an individual or group to administer a section of land in the name of the crown. As a rule, such charters are issued for land which is not within the boundaries of the kingdom, but which is claimed by the throne. As such, a Royal Charter may give away land which is also claimed by another government. In such cases, open warfare or occasional skirmishes are possible.
A land grant is issued to characters who have done some great service to the crown. As a rule, they are accompanied with a patent of nobility for the rewarded individual. Land acquired in this fashion is still assumed to belong to the person issuing the grant, but the vassal is given free charge over all that occurs on it. This is the traditional means by which feudal kingdoms are split up into manageable sections. Since a land. grant is normally within the borders of the kingdom, it is seldom disputed.
One of the more infamous means of coming into possession of land on which to build a castle is by taking it with force. Examples. of such actions might include the "liberation" of a land which is rightly the king's (in his opinion) but which has been taken over by another state and the taking of land held by a nation of opposing alignment. As a rule, land taken in this manner will eliminate any chance of popular support for the castle construction project. In game terms, this means that worker morale (defined in the next section) will never be better than "average".
In some cases, it may be possible to buy land from a king or other individual on which to build your castle. Since many feudal kingdoms do not recognize the right of an individual (other than the king) to own land, this is often not a possibility.
To determine the purchase price for land (when it is available) start with a base value of 100 gold pieces per acre for undeveloped property. Divide the base value by the Production Modifiers (see the next section) for its climate, geography, and ground cover. Developed land will be more expensive, with property in a town costing perhaps 10 times the computed value and land in a major city fetching a price upwards of 100 times its "true" value.
Persons buying land will want to keep in mind that they should, as a rule, buy enough land for the castle itself, all the farms required to support it, a small village for those who work the farms, and woodlands for hunting and future development. As you can see, buying land can become a very expensive problem.
Among adventurers and explorers, claiming land is a favorite means of setting up housekeeping. If the character or party are recognized as the first individuals ever to tame or explore a given region of the world, then they are free to claim it. If they are planning to establish their own country, the characters are free to claim the land for themselves. Of course, if someone else comes along and claims it as well (see claim jumping), then a battle may ensue. Hopefully, the characters are prepared for this and will be able to keep their attackers from defeating them.
If the players lack the resources or the desire to set up their own kingdom, they will want to claim the land in the name of the ruler they serve. By so doing, they are almost assured to receive a Royal Charter or land grant which lists them as the rightful rulers of the area. Kings and emperors will almost always look very favorably on those who work to expand their lands.
In regions which are only partially explored or which have been claimed by a rival government, it is possible to "claim jump". In short, a force moves in, makes their claim, and establishes a keep or village of some type as quickly as possible. They then attempt to hold the land, often asserting "squatter's rights" and fighting off attempts by others to reclaim their rightful territory.
Another possibility is the theft of land. Although it is obviously not possible to actually grab the land and run with it, there are many dishonest means by which ownership can be had. For example, a land owner could be forced into betting his land in a dishonest card game. When the last hand is dealt. he has lost. Falsified bills of sale or wills are another possibility. As a rule, only those of evil alignment will use such means to acquire land.
Although not a common practice, it is sometimes possible to lease property from a land owner. This is much like buying the land, but assumes that a monthly payment will be made to the lord-a sort of rent.
In return for his payments, the land is under the complete control of the leasing character. Often, a lease will be set up to allow the character a chance to begin building a castle before he has acquired the funds to buy the land outright. The price charged for a land lease is highly negotiable, and DMs should base the monthly payment on the value of the land (as computed in the section on buying land) and the perceived wealth of the character.