The reported members of the Illuminati include the royal families of several nations as well as a large handful of prominent leaders in finance, technology, and the upper levels of various national governments. This secret organization has long been a subject of speculation and conspiracy theory among researchers who attempt to draw connections between the Illuminati and major world events throughout history. Although membership in this group is often thought to be conditional on royal bloodlines, several famous non-royal names are included in available membership lists. The main purpose of this secret society is reportedly to create a single global government known as the New World Order.

Some well-publicized theories about Illuminati membership claim that it is only open to people born into one of 13 powerful families, some of which have famous names such as Kennedy, Rothschild, and Rockefeller. Various theorists report that no outsider can join the upper ranks of the Illuminati, which is a factor that sets the organization apart from other known secret societies. Since the highest-ranking members exert such extensive control behind the scenes of governments and economies, membership is strictly limited to new members who are born into the right family with the right bloodline.

Common threads among the Illuminati members are notable wealth, power, and success. Several Chief Executive Officers (CEOs) of multinational corporations such as Bill Gates of Microsoft are counted among its mid-level members. While they may not belong to royal bloodlines, these members are said to be recruited and trained from early ages in order to ensure their loyalty and dedication to the Illuminati's purpose of eventual world control. In exchange for unwavering loyalty, the organization gives its recruited members access to secrets that facilitate their vast accumulation of wealth and domination of certain industries.

Founders of the United States such as Benjamin Franklin and Thomas Jefferson are also counted among members of this secret and powerful organization. Many theorists connect the establishment of the US as a new nation to calculated strategies for a new world government. Some researchers claim that every US president has belonged to the Illuminati and only rises to power thanks to the organization's various maneuverings. A frequently-documented conspiracy theory claims that high-ranking members actually control presidential elections as well as both major political parties. Even though the word literally means "People of Light", several theorists attribute the Illuminati's power and influence to the practice of black magic and other occult rituals.