"The plot is set in a fictional history of real-world events and follows the centuries-old struggle between the Assassins, who fight for peace with free will, and the Templars, who desire peace through control."
"Samples that were taken from Desmond Miles' body in the moments after his death have allowed Abstergo Industries to continue exploring his genetic memories using the Animus' newfound cloud computing abilities. The unnamed player character is hired by Abstergo Entertainment, from their Montréal headquarters, to sift through the memories of Edward Kenway, an eighteenth-century pirate, the father of Haytham Kenway and the grandfather of Ratonhnhaké:ton. Ostensibly, this is to gather material for an Animus-powered interactive feature film. In reality, Abstergo—the Templars of the present time—are searching for a First Civilization structure known as the Observatory, and are using Edward's memories to find it."
"... the Observatory, a First Civilization device which can monitor anyone anywhere in the world when provided a blood sample, which they intend to use to spy on and blackmail world leaders."
- Excerpt from Assassin's Creed IV: Black Flag's Wikipedia page, accessed September 24, 2020