I keep thinking "oh, this is a nice big topic to wax long-winded over"... and then realise that I don't precisely know what "my" Castle world is. Is it the Castle world reflected in Grandfather's Tale
? Is it the way they fit together in my childhood Lego stories--partially rewritten in past years for personal pleasure? Or is it the way they get played with... or would if I ever did that anymore? Insofar as these "worlds" do not quite overlap, it's a bit of a question.
So... bear in mind that what you are about to read is merely the variant I am most content with.
ROYAL LION REALM: Royal Knights, KK1, KK2, and Kingdoms: four kingdoms (with various semi-independent lordships, especially in Morcia, the southern realm) under one High King (the Royal Knight king, for nostalgia reasons). Occasionally riven by civil war, more often endangered by outside forces, especially the Fright Knights and Dragon Masters. The Bull Knight mercenaries are based in the north kingdom (KK1), and are variously servants of the Crown, or enemies, as the money-trail indicates.
LIONDOM: Classic Lion Knights even older classic figs, including their erstwhile vassals, the Black Falcons. Liondom was the oldest Lion-bearing realm, but lost the title of High King to the Royal Knights, but became independent soon after. Liondom includes the largest portion of the Dark Forest (which also goes into the Black Knight realm and the Royal Lion realm), and are often at odds with the Forestmen who live there. In addition to the Forestmen, the Lions are often at war with the Black Falcons and/or Black Knights. Their king is the "prince" with the original jousting set, and his royal guard are the Crown Knights of the Yellow Castle. The various Lion and Falcon barons exert considerable power.
BLACK KNIGHTS: Under the rule of the Black Monarch, including the Kingdoms Dragon Knights, the Black Knights are the rivals of Liondom, and have often supported the Black Falcons in making trouble. Their west marches nominally include the Dragon Masters, but these wilder warriors listen only to Majisto, the most powerful mage in the Castle realms, and are essentially independent. The Wolfpack mercenaries are based on an offshore island in this realm, and are NOT in good standing with the Black Monarch.
CROWNIES: Located across the straights from the other Castle realms, this powerful and militaristic realm faces perpetual war with the undead skeletons of the Sorcerer-King, and with the trolls native to their northern mountains. Originally a Dwarf-realm, humans have been dominant for several hundred years, originally imported/hired to fight the skeletons.
DRAGON MASTERS: Mostly independent Black Knights under the command of Majisto, and typically enemies of the Royal Lion Kingodm.
FRIGHT KNIGHTS: Clans related to the Dragon Masters, but farther south (along the Royal Knight border), often at war with the Royal Knights.
SHADOW KNIGHTS: Fright Knight/Morcian interbred nation, small, but independent because of its easily defended mountain position. Often allied with the Fright Knights against the Royal Lions.
VIKINGS: Noble but barbaric raiders who live on the coasts west of the skeleton lands, and north of the Crownies. They raid the Black Knight, Crownie, and Royal Lion coasts.