Hellsing Ultimate Fan Guide :

Hellsing is set in a horrific version of the modern world where undead walk the night in search of blood and power. The time frame is current-day England, with a focus on London. The primary emphasis of the series is the Hellsing Organization--a secret group working with the English government to keep the undead menace in hand. The primary character of the series is Arucard, a supposedly ancient vampire who works with the Hellsing Organization to destroy lesser members of his own kind.