Officially, The Masquerade is the vampire survival strategy of hiding their true supernatural nature from humanity, blending in with mortals, and promoting the belief that vampires don't exist. Unofficially, it also refers to a vampire's effort to cling to their humanity and convince themselves that they are not the monsters they have become.
The Old MasqueradeEdit
For most of history, the Masquerade was considered more of a suggestion than a strict policy—until the mid-thirteenth century, when the Catholic Church became aware of vampires and the Roman Inquisition began actively hunting the undead. Although a single vampire was stronger than any given human, mortals vastly outnumbered vampires, and could operate during the day when vampires were vulnerable and helpless.
At this point, the Camarilla made the Masquerade its primary policy, believing it to be the only way vampires could survive. The Masquerade was strictly enforced, with any breaches (such as publicly drinking blood, using supernatural powers, etc.) being punished quickly and harshly. Repeat offenders had blood hunts issued against them.
The Sabbat, on the other hand, wanted to tear down the Camarilla and their Masquerade and rule humanity openly... even while benefiting from the success of the Masquerade making it easier for them to avoid detection and feed off of mortals.
The Masquerade was shattered by the Bug landing in Rio de Janiero in 2001 and the paradox backlash explosion that destroyed it. This triggered Gehenna, and humanity suddenly became very much aware that magick and supernatural creatures like vampires, ghouls, werewolves, and mages existed. In addition to the antediluvians fighting for control of vampire society and all humanity, they also had to fight the mage factions and werewolf tribes, both of which were also waging their OWN internal battles for control of their group. The result was a bloody, destructive, and chaotic free-for-all that lasted for eight long years. Although the Technocracy mages won a narrow victory, all sides were decimated and exhausted.
The New MasqueradeEdit
After Gehenna, although many vampires retreated to safe havens (first the Wraithlands, later the Kingdom of Enoch and Wilke's Star), many others remained among humanity. Their survival now depended on a new Masquerade that was even more crucial than before. Now that humanity was aware of vampires' existence, knew the telltale signs to look for, and posted etheral scanners at every security checkpoint, it was more difficult than ever for a vampire to pass for human. Things grew even worse after 2209 when Crusader Teams were formed, armed with plasma weaponry that caused aggravated damage, with the express purpose of hunting down and destroying vampires.
Currently, vampires that still reside on human-occupied worlds are masters of the Masquerade, armed with sophisticated magickal and technomagickal equipment to disguise their true nature, and operating from the shadows of society through trusted intermediaries and anonymous computer networks.