- "Better to die enlightened, than to live in ignorance."
- ―Nicolaus Copernicus.[src]
Copernicus was the youngest of four children. Like his brother, who became a priest, and his sister, who became a nun, Copernicus enrolled in a humanist education to become a priest, studying Aristotle, Ptolemy and others at the University of Kraków. After graduating, Copernicus expected to be appointed as a clergyman in Warmia, but travelled to Italy to study law first.
While learning in Italy, Copernicus found he preferred attending humanities lectures and discovered his passion, astronomy. His mentor was Domenico Maria Novara da Ferrara. In 1500, Copernicus visited the Vatican, where he was introduced to the Templar Order. Upon joining them, he was later told that they wanted him to keep his discoveries secret.
A day after, however, he enlightened the public on science and mathematics at the Il Campidoglio, encouraging them to question past teachings, as he could not keep his findings to himself. He went on to urge the crowd to visit him or his fellow scholars if they wished to know more.
As soon as the Borgia – the leading house in the Templar Order – heard of this, they sent their guards to kill Copernicus and the other scholars. The Assassin Ezio Auditore da Firenze watched the scene unfold and, upon realizing their common enemy, came to Copernicus' aid.
Copernicus admitted his affiliations to the Templars to Ezio, though the latter was willing to help Copernicus reach a safe location. Upon arriving in a secluded building in the Antico District, Copernicus asked Ezio to deliver some documents to his fellow scholars, which would inform them of the danger they were in. Though doubtful if he could trust him, Ezio agreed, and aided most of the scholars in going into hiding.
The Assassin returned some time later, and by then, Copernicus had concluded that the Master of the Sacred Palace was most likely behind the plot to kill him. Ezio sought out the Master and heard from him that there were five executioners walking around Rome, searching for the scholars. Ezio rushed to take these executioners down, and returned to Copernicus with the confirmation that his suspicion had been correct.
Copernicus, however, was persistent in going out into the open to study a lunar eclipse. The Master of the Sacred Palace seized this opportunity, and sent a Papal Guard to kill him. Ezio followed and killed the Master of the Sacred Palace before returning to Copernicus, with whom he took down the assailants. The pair then went their separate ways, with Copernicus staying behind to study the eclipse.
Following their encounter, Copernicus became an ally of the Assassin Order, and was assisted in further astrological studies with Novara via the Order's protection, with one instance including the Assassins Francesco Vecellio and Cipriano Enu.
Copernicus left Rome a year later, and applied for an extension of his education abroad to learn medicine in Padua. While there, he learned Greek, adding a fourth language to the list of ones he was fluent in, after Polish, German and Latin.
In 1503, Copernicus returned to Prussia and worked as secretary for his uncle, Lucas Watzenrode, the Bishop of Warmia. In his spare time, he pursued his astronomical interests, drafting his heliocentric theory and observing the sky at night. His theories were not published until shortly before his death in 1543.