The game is included in Ubisoft+ , a monthly subscription service that allows you to play their entire library.
If you are researching the secret society (Yale University) or general pirate history: Skull and Bones Free Download
Sites like Project Gutenberg or Internet Archive offer free downloads of historical texts regarding 18th-century piracy (the "Golden Age") and academic papers on secret societies. The game is included in Ubisoft+ , a