The 32-year-old dancer has become one of the most famous ballerinas in the United States during her 14 years with ABT. She has presented at the Tony Awards, was honored as one of Time's 100 Most Influential People, and has written two books -- Firebird and Life in Motion: An Unlikely Ballerina.
The promotion, which means more money and bigger roles, has been a dream for Copeland, as she made known in Life in Motion.
"My fears are that it could be another two decades before another black woman is in the position that I hold with an elite ballet company," she wrote in the memoir. "That if I don't rise to principal, people will feel I have failed them."
The announcement was captured in an emotional video posted to Instagram.
In 2012, Copeland was close to being promoted before she was setback by injury. Along with Copeland, dancers Stella Abrera, Maria Kochetkova and Alban Lendorf were also named principal dancers at ABT.
Under Armour, who touts the dancer as one of their spokespeople, tweeted their congratulations to Copeland, writing, "History is beautiful. Congrats @Mistyonpointe on being named American Ballet Theatre Principal. #IWILLWHATIWANT"
Arthur Mitchell first broke the color barrier in 1962, becoming a principal dancer at New York City Ballet.
"I never saw a ballerina who looked like me before," Copeland told Time, noting that black ballerinas like Raven Wilkinson have mentored her. "I'm here to be a vessel for all these brown ballerinas who have come before me."