The Demon Castle War
From Castlevania Wiki - Forbidden Library
The Demon Castle War, also known as The Battle of 1999, is an important sequence of events in the Castlevania timeline, at the conclusion of which Dracula is finally felled by the Belmont clan, once and for all. However, for all the importance this sequence of events holds, comparatively few details are available concerning them at the moment.
Dracula rose in 1999 to wage war on humanity, but was defeated for good by Julius Belmont, and his Castle sealed in an eclipse by the Hakuba clan. At the same time, Graham Jones, Dario Bossi and Dmitrii Blinov were born, leading each of them to believe they were the reincarnation of Dracula, though they were misguided in their beliefs, as Soma Cruz was ultimately shown to be the true reincarnation of Dracula.
Dracula's resurrection and defeat is said to be predicted by Nostradamus, who also predicted a new master would arrive in 2035 and inherit all of Dracula's powers.
The only known participators in the war are Julius Belmont and the Hakuba clan. However, Julius mentioned that there were others helping him, and certain enemy descriptions imply the military was involved.
At this time, it is unknown as to whether or not the Demon Castle War will ever be fully elaborated upon or featured in a Castlevania title.