Members of the new U.S. Congress were sworn in Thursday as the most diverse group of lawmakers in its history.

The 116th Congress began its session Thursday as well, with a House of Representatives that is now comprised of majority Democrats.

A record number of women were sworn into the House, 102, including 35 who were newly elected in November.

The new congressional session, which will run until January 2021, also sees many firsts, with the first Muslim congresswomen, Native American congresswomen as well as the youngest member in the history of Congress.

First Muslim women in Congress

Rashida Tlaib and Ilhan Omar made history Thursday, becoming the first Muslim women sworn into Congress.

Tlaib, a Palestinian-American Muslim, wore a traditional Palestinian dress and made her oath on a copy of the Quran originally owned by Thomas Jefferson, the third President of the United States.

She joined Omar, her Democrat colleague, as the first Somali-American and first congresswoman to wear a hijab, or headscarf.

Omar came to the U.S. more than two decades ago as a refugee.

"Twenty-three years ago, from a refugee camp in Kenya, my father and I arrived at an airport in Washington DC," Omar said on Twitter, posting a photo of her father and her smiling with suitcases. "Today, we return to that same airport on the eve of my swearing in as the first Somali-American in Congress."

Last year, a record 90 Muslims contested the polls since the Sept. 11, 2001 attacks, according to Jetpac, an organization that helps Muslims run for political office.

Youngest member of Congress

Alexandria Ocasio-Cortez, 29, became the youngest woman to be sworn in to the House of Representatives. She represents New York's 14th congressional district, which includes parts of Queens and the Bronx.

The Latina pulled off an upset victory earlier this year in a primary race against Democratic incumbent Joe Crowley. Ocasio-Cortez’s victory shot her into the national spotlight with questions whether the far-left wing of the Democratic party she represents is posing a viable challenge to the establishment.

First Native Americans sworn in

Sharice Davids, a Kansas Democrat and member of the Ho-Chunk Nation, along with Deb Haaland, a Laguna Pueblo from New Mexico, became the first Native American congresswomen to serve in the House.

Their elections serve as a significant milestone for the indigenous community in America, who only became citizens in 1924, and were only given voting rights in 1948.

Other notable firsts in Congress

And Ayanna Pressley is the first black congresswoman from Massachusetts, adding to the House's diverse array of members.

Other firsts include Republican Marsha Blackburn, the first female senator from Tennessee; Democrat Kyrsten Sinema, Arizona's first female senator and Democrat Jahana Hayes, the first black congresswoman from Connecticut.