Kaldor is a land-locked feudal kingdom in eastern Hârn. Since its founding more than 500 years ago, external threats have been minimal but internal strife has been common. The current dynasty, Clan Elendsa, has sought to uphold the traditional principles of feudalism, chivalry, and royal justice. King Miginath Elendsa is popular with the common people because he has kept the kingdom prosperous and at peace.

King Miginath is in poor health and has never married, leaving the succession a matter of contention between three bastard sons and a score of nieces and nephews. Intermarriage with other noble clans and the granting of royal offices in exchange for concessions has created a complicated web of alliances that may discourage a civil war when the king dies. While he lives, the factions plot and scheme for advantages.

Much of the land claimed by Kaldor is controlled by tribal nations, some peaceful, others decidedly less so. The kingdom maintains two standing armies on the marches, but relations with the tribes are not always warlike. A few hardy miners, trappers, and explorers venture in the wilderness, and tribesmen are a common sight in border settlements.

The capital, Tashal, is an important economic hub. Caravans converge here from all corners of Hârn: from Orbaal down the Fur Road, from Azadmere along the Silver Way, from Thay and the Lythian continent via the Genin Trail, and from western Hârn by the Salt Route.

The Kingdom of Kaldor module is supplemented by other Columbia Games publications, including keeps, castles, and adventure sites, and provides a variety of opportunities for adventure.