Kate McKinnon was born on January 6, 1984, in Sea Cliff, New York, to parents parent educator Laura Campbell and architect Michael Thomas Berthold1. McKinnon had a natural ability for music and performance from a young age, beginning to play the piano at age five, the cello at twelve, and the guitar at fifteen1. Her talent for accents began in fifth grade, when she faked a British accent to audition for "Queen of Reading Week," which she credits as the beginning of her comic career. McKinnon attended North Shore High School and graduated in 2002 before enrolling at Columbia University1. She co-founded the Tea Party comedy club at Columbia, which focuses on musical improv comedy, and graduated with a theatrical degree in 20061. These early experiences with music, accents, and comedy established the groundwork for McKinnon's subsequent success in sketch comedy and acting.

Kate McKinnon's sketch comedy career began with her appearance on "The Big Gay Sketch Show," which ran on Logo TV from 2007 to 20101. This LGBT-themed sketch comedy program, produced by Rosie O'Donnell and directed by Amanda Bearse, gave McKinnon an opportunity to display her comic abilities early in her career1. McKinnon stood out among the cast at the age of 23, showing the same scene-stealing skills that would later become her signature on "Saturday Night Live"2. The show included a number of sketches with LGBT themes or twists, such as parodies of vintage sitcoms and original character-driven comedy13. McKinnon's performances in "The Big Gay Sketch Show" paved the way for her future success, honing her skills in character work and impressions, which would become key to her comedic approach24.

Kate McKinnon's appearances on "Saturday Night Live" (SNL) from 2012 until 2022 were distinguished by her outstanding aptitude for celebrity impressions. Her impersonation of Hillary Clinton during the 2016 presidential race became one of her most memorable performances, mimicking the politician's mannerisms and speech patterns with amazing realism1. McKinnon's flexibility was evident in her various impersonations, which included Justin Bieber, Ellen DeGeneres, and Ruth Bader Ginsburg1. Her ability to change into various characters made her one of SNL's most valuable actors, with her impressions often becoming show highlights (2). McKinnon's talent for mimicry and character work enabled her to add depth and humor to her representations, making even excessive caricatures appear grounded and approachable1. Her talents to SNL's political satire and pop culture parodies cemented her place as one of the show's most memorable cast members in the 2010s1.