The Democratic representative won the Georgia 6th District in a narrow, upset victory over Republican incumbent Karen Handel.
Lucy McBath is officially a Congressional representative.
The Democrat was sworn in to the 116th Congress, Jan. 3, joining one of the most diverse U.S. House cohorts in history.
McBath, along with her fellow freshman representatives participated in a ceremonial swearing in at the U.S. Capitol Thursday.
More than 100 women were sworn into the House of Representatives - a new record. But there are also other historic firsts - including for indigenous, Muslim and LGBTQ representatives.
McBath will represent Georgia's 6th District that covers north Atlanta, taking over from previous Republican representative Karen Handel.
The Democrat narrowly defeated Handle - who had just been elected to the post in a June 2017 special election to replace predecessor Tom Price - in the Nov. 6 election.