Alldras is a vast, medival world devided into five different kingdoms: the desert of Nuada, the open plains of Calavion, the snowy mountains of Rohadan, the Leviathan Isles and the technologically advanced, proud realm of Cardas, the latter being the seat of the Empress of Alldras, Nyr Leonheart.
She came to this world through a rift between dimensions alongside with her Knights, powerful, magic wielding entities others would consider demons. She hailed from a world where technology and magic were combined in damnable processes, forging weaponry, armor and even reforging the very soul and body of her vassals to powerful beings, called Infernals.
Even though they were few, Nyr quickly conquered three of the five kingdoms: Rohadan, Calavion and Cardas. Either by force, or by diplomacy. The lords of the different realms either bent their knee, or their heirs did once their fathers were dead, or, if there was noone left, one of nyrs Knights became new Lord Regent of the kingdom in question.
Now, the "Empress of Hell" resides in her abyssal citadel, a giant tower resting above the rift between worlds she ventured through, granting those who prove themselves worthy to her the powers of the molten throne via her abyssal forge. Even though she rules over all of the five kingdoms, she still keeps other Houses and Lords around as Lord Regents of their respective realms. But truth be told: Most people in Alldras do not even recognize her presence all that much, except for House Leonhearts banner... and her knights roaming the kingdom.