Historical relationship
During its brief expansion, the Bavarian Illuminati recruited partly through environments connected to Freemasonry. Some individuals participated in both worlds. That overlap is historically documented in broad outline; it does not collapse the two into one society.
Similarities
Both used graded membership, secrecy, and symbolic language typical of eighteenth-century fraternal and intellectual associations.
Differences
Freemasonry has a longer, broader, and differently structured history across many jurisdictions. The Bavarian Illuminati was a specific short-lived order with its own founder, program, and suppression story.
Later popular culture
Conspiracy literature often merged lodge imagery with Illuminati panic. Entertainment continues that fusion. Critical readers should ask which institution, place, and century a claim actually concerns.
Related reading: Bavarian Illuminati, conspiracy theories, blog article.