- "Wherever you go, you are bound to find one of us working in secret... in the court of a monarch, for instance."
- ―Luis Santángel to Ezio Auditore, 1491[src]
Luis de Santángel (unknown – 1498) was a baptized Jew born in Valencia and the finance minister of King Ferdinand II. He assisted the explorer Christopher Columbus in his negotiations with Queen Isabella I of Castile to acquire funding for his voyage across the Atlantic Ocean, ultimately financing most of it himself. As a member of the Spanish Brotherhood of Assassins, he aided Ezio Auditore da Firenze and Raphael Sánchez in foiling a Templar conspiracy in the Granada War. Late in his life, he turned against Queen Isabella and plotted to poison her when she became lost to Templar influence though this assassination was only completed after his death.
Joining the Assassin Brotherhood some time prior to 1491, Luis and fellow Assassin Raphael Sánchez developed close ties with Queen Isabella and King Ferdinand to prevent the Templars from dominating the monarchy. While Raphael became the royal treasurer of Castile, Luis was appointed as Ferdinand's finance minister though he was forced to convert from Judaism to Christianity by Grand Inquisitor Tomás de Torquemada in the process.
Protecting Christoffa in Italy
- "I represent a man who has come to Venezia on a foolish errand. I fear his life is in danger, but he refuses to listen to my counsel."
- ―Luis upon meeting Ezio for the first time, 1491[src]
Though he was not aware this sponsor, who he knew only as "the Spaniard", was the Templar Grand Master, Luis's intuition led him to suspect the meeting was a trap. Despite this, the desperate Christopher refused to heed his warnings. Left with no other choice, Luis accompanied him from Spain to Italy. He had meant to enlist the Assassins for help protecting Christoffa from any dangers, but by then the Spanish Inquisition had purged most of them throughout the country.
Thus, when he arrived in Venice, he met with the leader of local thieves' guild and fellow Assassin, Antonio de Magianis, to request help for the protection of Christoffa, having already contacted Antonio ahead of time from Spain. Antonio called upon Ezio Auditore da Firenze for the job. Because he regarded this as mercenary work and did not know that Luis was an Assassin, Ezio was initially reluctant, but he accepted after he heard that Borgia was involved. He arrived just in time to rescue Christoffa; Rodrigo himself never showed.
Grateful for the aid, Luis and Christoffa prepared to leave Venice, only to find that their hostel had been raided by the Templars. This would have been of little consequence to them if not for the fact that the prized atlas was still hidden inside. They had notified Antonio that they would meet Ezio in the garden district should anything have gone wrong with Christoffa's meeting, and when Ezio arrived as requested, they informed him of their problem. Reluctant yet again, Ezio emphasized that this was to be their last favor and left to recover Christoffa's atlas.
Luis and Christoffa then waited at the Venetian harbor for Ezio to return with the atlas. When the Florentine Assassin did so, he advised that they should bring their own protection the next time they traveled to Italy, and it was then that Luis informed him that the Assassins throughout Spain have been targeted by the Inquisition, leaving none left with Ezio's martial expertise. The news shocked Ezio, not least of all that Luis knew of his order, but Luis decided against revealing his affiliation outright, only explaining that many of his friends had been arrest by the Inquisitors.
Mission to Granada
Alongside Christoffa, Luis returned to Spain, where later in the year he was notified by fellow Assassin Raphael Sánchez, then working with Ezio in Aragon to rescue the Assassins from the Inquisition, that Ezio might be joining them on their mission to Granada. Meeting with Raphael on the outskirts of Granada, they awaited Ezio's rendezvous. The Florentine was surprised to be greeted by Luis, and it was here that Luis at last revealed to him that was an Assassin as well.
He then guided Ezio in eliminating the Templars' operations in Granada, tasking him to kill a Templar spy that had been feeding Emir Muhammad XII false information to convince him to prolong the war. After Ezio assassinated the spy in a Spanish camp dug deep into the hills, he returned to reconfirm Luis's intel with what he had overheard from the spy. The group deduced that the Templars hoped to prevent Christoffa's voyage by draining Castile's funds through a costly war, allowing them to send their own expedition west first. Without further ado, Ezio left to infiltrate the Alhambra to persuade Muhammad XII to surrender and end the war, using the secret route through the catacombs favored by the spy.
In the meantime, Luis and Raphael traveled to Granada overland where they met up with Christoffa as well. The moment Muhammad XII capitulated, the impatient Christoffa rushed to pressure Queen Isabella to sponsor his voyage immediately, much to Luis's frustration, as the timing was inopportune, with Queen Isabella just meeting with the emir to negotiate terms. Ignoring Luis's pleas to not be so rash, Christoffa stormed off to the queen. It was just then that the Assassins were alerted by a civilian crying that the Spanish were razing the city to the ground. Like usual, Luis and Raphael dispatched Ezio to deal with this crisis. Likewise, they would defer to Ezio once more when Inquisitors under Juan de Marillo began arresting citizens throughout the city when it was formally transferred to Castile.
Funding Christoffa's voyage
After the end of the Granada War, Luis introduced Ezio to Queen Isabella, as the hero that negotiated Muhammad XII's surrender. Despite their hopes that Queen Isabella would agree to fund Christoffa's journey in gratitude, she declined as the war had just ended and funds were still low. She assured them that King Charles VIII of France had already offered his sponsorship, and that Christoffa had left for France that very morning.
Rather than being consoled by the news, Luis was in a panic, knowing full well that this was almost certainly a Templar trap. Weary of all the trouble, Luis resigned to financing Christoffa's voyage personally as a last resort. Meanwhile, Ezio hurried to intercept Christoffa on the road to France, finding him just in time to save him from a murderous Templar and persuaded him to return with the news that Isabella had changed her mind.
This news was preemptive, as Luis had just successfully convinced Isabella when Christoffa and Ezio walked into their meeting. The queen was at last convinced to help finance the voyage by Luis's proposal to cover half of the entire cost.
Templar assassination attempt
- "Contemptible man! He already forced a conversion from me... now I suspect the Templars are feeding him orders."
- ―Luis on nearly being murdered by the Inquisition, 1492[src]
As Luis predicted, Inquisition soldiers had raided Raphael's house as well and were seconds away from killing him when Ezio arrived and saved him. Following Luis's orders, Ezio proceeded to Torquemada's palace to eliminate him once and for all though Raphael advised that he confronted him first and goad him into revealing the extent of his association with the Templars. Ezio would follow Raphael's instruction at the cost of a successful assassination and by Torquemada's veiled response, would incorrectly conclude that the Inquisitor-General, in reality a Master Templar, was merely a fanatic manipulated by the Templars without knowing it.
Assassination of Queen Isabella
Luis continued serving the Spanish royal house for many years, always maintaining a watchful eye on Queen Isabella. As a devout Catholic, the queen was often swayed by the religious extremists in her court, who sought to intensify the Inquisition. Luis strove hard for many years to counteract the influence that the Inquisition wielded over her, but when Rodrigo Borgia, the Grand Master of the Templars, was elected Pope on 11 August 1492, the Templars made phenomenal gains in their power over Isabella. Isabella trusted the Pope, and Rodrigo exploited this to continuing wielding the Inquisition as a tool against the Spanish Assassins.
Eventually, Luis lost all hope for Isabella and plotted to assassinate her by poisoning her slowly through the administration of periodic small dosages. For this, he employed the aid of a palace servant to serve as the poisoner and recorded all the details of the plot in a secret journal. As with many Assassin texts, its true content was written with an invisible ink that only those with Eagle Vision could see. When he died in 1498, however, his plan had yet come to fruition, in part because the dosage he and his accomplices calculated was insufficient. The palace servant was unable to continue the poisoning of Isabella because without Luis, she did not know how to craft the poison.
With his death, there was no one to inform the other Assassins of the Templars' activities in the royal house. Therefore, Ezio Auditore sent his apprentices to Spain to recover Santángel's journal around 1503. This they accomplished, despite narrowly being caught by a group of guards, who investigated the journal and thought it held nothing but religious text. While they initially suspected that Luis's poisoning of Queen Isabella stemmed from a desire to avenge the deaths of his family at the hands of the Inquisition, after their own investigation into Isabella's activities, they came to approve of his plot. Contacting the palace servant that acted as the poisoner, they requested that she finish the task. The servant was hesitant at first but agreed when they appealed to her bond with Luis, as Luis had wrote highly of her in his journal and she still mourned his passing. Supplied with the poison—with twice the dosage as before, the servant would successfully kill Isabella in 1504.