"Jennifer is a bright young coach and will be a great addition to our staff," head coach Ron Rivera said in the team's release. "Her familiarity with my expectations as a coach and my firsthand knowledge of her work ethic and preparation were big factors in bringing her to the Redskins."
Rhiannon Walker of The Athletic first reported the hire on Saturday.
King is the first full-time African American female coach in league history and the fourth woman with a full-time assistant job overall, per Walker. Collette Smith was the NFL's first black female coach, serving as an intern with the New York Jets in 2017.
King served as an intern for Carolina from May through August 2017 under then-Panthers head coach Ron Rivera, who now leads the 'Skins after being hired in December.
Since then, King worked as an assistant wide receivers coach for the now-defunct Alliance of American Football's Arizona Hotshots and as an offensive assistant for Dartmouth College.
Both teams excelled in 2019: The Hotshots co-led the AAF West division with a 5-3 record when the league folded. The Big Green went 9-1 (6-1 Ivy League) and finished second in their conference.
Prior to her Panthers' coaching stint, King played in the semi-pro Women's Football Alliance, winning three championships. She also coached youth and high school teams, per Walker.
As has been the case throughout her coaching career, King will work on the offensive side of the ball, specifically with Washington's running backs.
She joins Tampa Bay Buccaneers assistant defensive line coach Lori Locust, Bucs assistant strength and conditioning coach Maral Javadifar and San Francisco 49ers offensive assistant Katie Sowers as the only women working as full-time NFL coaches.