List of impostors

An impostor (also spelled imposter) is a person who pretends to be somebody else, often through means of disguise, deceiving others by knowingly falsifying one or more aspects of their identity. This is in contrast to someone that honestly believes their false identity due to psychosis (break from reality), mistake (e.g. mistakenly switched at birth, or memory problems), or having been lied to about their identity by another (e.g. by a parent, or kidnapper).

They may lie about their name, rank or title, profession, education, identity of family members or friends, social class, notoriety or influence, life experiences, abilities or achievements, their health history or disability (or that of their family members), citizenship or club membership, racial or ethnic background, religious or political affiliation, wealth or property ownership, tenancy or residency, past or current employment, charitable contributions, criminal or civil court history.

Many impostors try to gain financial or social advantages through social engineering or through means of identity theft, but also often for purposes of espionage or undercover law enforcement. Their objective may be one of sexual gratification, giving a false name, false claim of being single or unwed, and/or false age in order to hide adultery, bigamy, or to catfish (e.g. a pedophile pretending to be a youth online).

Those in witness protection, those fleeing abusers or persecution, and criminals evading arrest may also assume a false identity.

Economic migrants may pose as tourists (visitor visas) or as international students (international student visas with a non-accredited university or college). As countries, like Canada, decrease their international student quotas, international students may imposture as asylum claimants.

Some impostors may do it for pathological reasons, such as having a personality disorder that involves an excessive need for attention and emotional reactions from others (be it praise and/or sympathy), an excessive sense of self-importance or being special, an excessive sense of entitlement, an excessive need to control others, a lack of remorse or emotional empathy, chronic and frequent exaggeration or lying about one’s abilities or life events, and exploitativeness. These psychological conditions may include narcissistic personality disorder (NPD), antisocial personality disorder (psychopathy and sociopathy), Munchausen syndrome (factitious disorder imposed on self) and Munchausen-by-proxy (factitious disorder imposed on another).

As part of humorous stunts and media pranks, protesters have also engaged in imposture, often revealing their true identity at a later time.

Many women in history have presented themselves as men in order to advance in typically male-dominated fields. There are many documented cases of this in the military during the American Civil War. However, their purpose was rarely for fraudulent gain. They are listed in the List of wartime cross-dressers.