New to Assassin’s Creed and need to jumpstart your way in? Long-time player of the games and completely lost by the story? Maybe you even think you’ve got a good handle on the wider story and just want to make sure. Well, here’s the complete summary of the game plot and all of the supplemental material to give you a more complete understanding of the Assassin’s Creed universe.
As usual, we eagerly welcome any feedback you might have for us, such as additions, changes, and especially any sections that could be streamlined further.
Note: This is the ultimate spoiler of everything ever, as it takes the pieces from all the games, books, movies, etc., and strings them into one continuous narrative.
All images are from assassinscreed.wikia.com unless noted otherwise.

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1. Stay your blade from the flesh of an innocent.
2. Hide in plain sight.
3. Never compromise the Brotherhood.
Nothing is true, everything is permitted.
-The Assassin’s Creed
First!
Humans didn’t evolve over millions of years from chimps. Rather, we were created by an advanced race of beings collectively called the First Civilization or Those that Came Before. They resemble humans but are taller, smarter, lived longer and were able to perceive changes in time and space. They were native to Earth, but we don’t know what they evolved from or if they were similarly created by an even older species. Humanity was created by fostering a huge evolutionary leap over an existing species on Earth and was specifically designed to be docile, stupid and sturdy beasts of burden. Key to this is a small neurotransmitter in every human brain, which receives signals from devices called Pieces of Eden.

Early humans being controlled by a Piece of Eden
The First Civilization used the Pieces to convince humans that they were Gods; thus the reason that most people worldwide created religion. In addition, most First Civilization activity centered on a area called Eden, thus the idea of the Garden of Eden emerged in human literature.

The actual Garden of Eden
Eventually, humans and First Civilization interbred to try and boost their small population. This inadvertently created a small amount of hybrid individuals who were not born with the neurotransmitter. War inevitably broke out when two hybrids named Adam and Eve instigated rebellion by stealing a Piece of Eden, also now referred to as an Apple of Eden. By sheer numbers, humanity overwhelmed their masters, but the conflict was cut short by a solar flare that penetrated during a period of weakness in Earth’s magnetic field, causing massive tectonic and geologic damage.

Earth after the solar flare (Picture center is the Sinai peninsula)
Both races ceased hostilities to concentrate on survival, and slowly rebuilt. The First Civilization was decimated to the extent that the gene pool was no longer viable, and they began focusing on trying to prevent a second such cataclysm. They began recording messages and signs waiting for humanity to develop the technology to understand it.
Only Two Things are Certain in Life: Templars and Assassins
History ever since has been a conflict between two groups called the Templars and Assassins. If you went to Sunday school, you might recall that Adam and Eve had two brothers named Cain and Abel, and that the former killed the latter. What they probably didn’t tell you was that it was over a Piece of Eden. Yes, this series… adapts history very often to fit this narrative, and the whole thing ends up sounding like downright conspiracy theory stuff.

Bet Jehovah’s Witnesses didn’t tell you THAT.
Cain thus became the first Templar, and his mark became their symbol. Their goal is to use the power of the Pieces of Eden to control humanity and thus create world peace. They believe human nature, if afforded freedom, will cause chaos and destruction. Their stated objective is to elevate humanity’s potential by unifying and harmonizing mankind’s goals and energy. Other hybrids opposed this viewpoint, arguing that no matter the cost, the total freedom of humans to make their own decisions and live with the consequences was paramount, forming the first Assassins. Hooray for moral ambiguity!
Over the next several thousand years, almost every major event in world history was the outward expression of the fight between these two organizations. Moses freed the Israelites and parted the Red Sea with a Piece of Eden. Templars gave Alexander the Great a Piece of Eden to create his empire, but he was poisoned by an Assassin. Qin Shi Huang, who unified and became the first emperor of China, was aided by the Templars and killed by an Assassin. The Roman Empire was heavily influenced by the Templars, and Assassin plots resulted in the deaths of Julius Caesar, Cleopatra, and the emperor Caligula.

Not the Son of God, just had a little help
Oh, and there was this guy called Jesus. You may have heard of him. No, none of that religious business. He was a poor carpenter who happened upon a Piece of Eden and used it to perform miracles and convince people he was the Son of God. The Templars figured this out and had him crucified using their Roman contacts to acquire it. John the Baptist also acquired a Piece of Eden, which he used to start his ministry, and after his death, St. Peter took it and used it to create the Christian religion.
لا شيء حقيقي وكل شيء مباح
(Nothing is true, everything is permitted)
It’s time for us to get to the first game! By the Middle Ages, both groups had publicly surfaced and were known by their names, but few knew of the underlying conflict between them. At some point, bad blood developed between Ṣalāḥ al-Dīn’s Saracens and the Assassins. He besieged their tiny fortress of Masyaf, but he probably should have expected that he might be targeted by the best killers around. He barely survived an assassination attempt, but was convinced to sign a truce. The cost? The life of the Assassin who tried to kill him, whose name was Umar Ibn-La’Ahad, the father of AC1’s protagonist, Altaïr Ibn-La'Ahad. For a kid whose mom died in childbirth and whose dad was killed in front of him when he was 11, that’s a tough childhood. Also, he has no friends.
Ok, he had one, then lost it pretty quickly. After his dad’s death, the Assassin that revealed his dad’s identity under torture confessed and committed suicide in front of him. Yeesh, give the kid a break, please? Worse still, that Assassin’s son was his best friend, Abbas. Or, at least, was, until Altaïr told Abbas the truth, and the latter lashed out, clearly not believing such cowardice was possible from his dad. This one-sided hatred continued on the down-low, but we’ll pick that up later.

Fast forward to Altaïr at 24, when Masyaf is besieged again (this happens somewhat often) by Templars, and Al Mualim, the Assassin leader, is taken hostage. Altaïr executes some super sneaky assassin maneuvers and kills the hostage takers. For his performance, Altaïr was promoted to Master Assassin. His first mission was to find a thing called the “Chalice,” rumored to be a powerful holy artifact. His travels took him through several cities and his blade in the guts of a dozen men. It turned out to be a she; the Chalice was actually a woman named Adha. She was then kidnapped by Basilisk, the Templar Grand Master, and escaped a pursuing Altaïr. He eventually located her, only to find and hold her lifeless body, and then proceed to kill everyone responsible. She was his first crush too. And you think you have it rough?
Disgrace and Redemption
The next year, 1191, Altaïr was tasked with securing an artifact from Solomon’s Temple in Jerusalem. Of course, as the best among his peers, he’s got a bit of swagger, and that results in him breaking all 3 tenets of the Creed and getting one of his team killed by the Templars, while both failing to kill the new Templar Grand Master Robert de Sable and losing the artifact. He returned to Masyaf empty-handed, but before he could sugarcoat the story, one of his team, sans an arm, came and told the truth. Suddenly the Templars attacked and besieged Masyaf (again). Altaïr snuck around and released a log trap onto the attacking forces, scattering them and forcing them to retreat. For flagrant disregard of the Creed, Altaïr was demoted to novice, and forced to earn his rank and his life back by finding the traitor who allowed the Templars through and assassinating nine men throughout the Holy Land.

Where’s the swagger now?
The Hitlist
All nine men had several things in common; they were all secretly Templars working together to get and exploit the Piece of Eden located by Robert de Sable in Solomon’s Temple. All were, after lengthy investigations conducted by Altaïr, killed. All nine had conversations in their last moments with Altaïr that forced him to question the purity and moral superiority of his motives and the nature of good and evil.

Tamir ibn Musa
Saracen weapons dealer, brutal and focused on max profit at all costs, based in Souk Al-Silaah, Damascus poor district
Garnier de Naplouse

Grand Master of Knights Hospitalier, doctor, fixated on knowledge, performed medical experiments on patients to gain knowledge, believed he was ultimately helping, located in Acre poor district

Talal
Slaver, excellent archery and athletic abilities, acquired beggars, whores, and thieves to sell or give to Garnier, based in Jerusalem rich district

Abu’l Nuquod
Rich “Merchant King” of Damascus, hates the poor and enjoys messing with them, loves to throw huge parties with lots of food, embezzles money from the city, said he could not support a war for a god that calls him an abomination, based in Damascus rich district

William of Montferrat
Crusader Regent of Acre while King Richard is out fighting, had a very bitter and public falling out with Richard, extremely focused on discipline and training was withholding food and money from citizens, says he did this to prepare them for the New World Order, based in Acre rich district

Majd Addin
Saracen Regent of Jerusalem while Salāh al-Dīn is out fighting, believed that everyone that was opposed to a new world order should be killed, contradicted and subverted Salāh al-Dīn’s tolerance in beliefs and religions, arguing that dissidents disrupted order and harmony, based in Jerusalem poor district

Hochmeister Sibrand
Grandmaster of the Knights Teutonic, desperate to preserve his power, constantly paranoid of coup attempts and plots against him, ultimately led to his death, said that he was scared because there was no afterlife for him, based in Acre middle district

Jubair al Hakim
Chief Scholar of Damascus, while originally a lover of knowledge and learning, hated it after becoming a Templar, believed it was the cause of discord, such as the Crusades, conducted large book burnings, based in Damascus middle district
Robert de Sable
Grand Master of the Knights Templar, the final target, and the leader of the nine, first assassination attempt was at Majd Addin’s funeral, but was a decoy, his lieutenant, Maria Thorpe
Robert was actually joining Richard and his forces at Arsuf, where he convinced Richard to ally with Salāh al-Dīn to eliminate the common threat: the Assassins, but Altaïr caught up and told Richard the truth, but Robert said the Assassins were skilled in lying. Richard “let God decide” through combat, and Altaïr beat waves of Robert’s men and ultimately Robert himself, but before dying, he told Altaïr that there were never just nine men. There were ten.

The 10th Man
Robert revealed as he died that Rashid ad-Din Sinan was the 10th man, and now with all of his fellow co-conspirators dead, he alone would have the knowledge and power of the Apple. In case you’re wondering who that is, you already know him, probably by his nickname, Al Mualim. Altaïr’s mentor and the leader of the Assassins.

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