Reese Witherspoon, Oprah Winfrey and Stephen King were among the celebrities who celebrated the inauguration of Joe Biden and Kamala Harris.
Mr Biden has become the 46th president of the United States after taking the oath of office at the US Capitol in Washington on Wednesday.
The star-studded ceremony featured performances from Lady Gaga and Jennifer Lopez.
Pop star Gaga sang the national anthem ahead of Mr Biden being sworn in.
The Democrat supporter wore a black and red ballgown decorated with a large gold dove of peace.
Before her performance, she said it would be an “honour” to sing at the ceremony.
Lopez, dressed all in white, sang This Land Is Your Land and America The Beautiful ahead of Mr Biden taking the oath.
Actress Witherspoon was among the stars to welcome Mr Biden and Ms Harris being sworn in.
“This show of unity is so inspiring,” Witherspoon wrote on Instagram.
Alongside a picture of Ms Harris, the Oscar-winner added: “Such a powerful moment for the women of this country to be represented in the highest office.”
Desperate Housewives star Eva Longoria welcomed the swearing in of the new president and vice president.
She tweeted: “Today, we make history! Today, we celebrate leaders like President Joe Biden and our first Madam Vice President, Kamala Harris.
“Today is only the beginning.”
Actress Kerry Washington said there is “much work to do” following the inauguration of Mr Biden.
She added on Twitter: “But TODAY I want to celebrate. And pray. And revel in our tremendous power (even against all odds) to make history happen.”
Broadcaster Winfrey said she was “in tears watching this extraordinary moment for women in the US and the world” alongside an image of Ms Harris taking the oath.
Talk show host Jimmy Fallon also congratulated the new president and vice president.
“I’m honored and proud to witness this moment in history,” he tweeted.
It author Stephen King tweeted: “This is a pretty beautiful event.”
Singer Dionne Warwick also shared a congratulatory message for Mr Biden and Ms Harris.
“What a happy day it is,” she added.
The Big Bang Theory actress Mayim Bialik also welcomed the incoming administration.
She tweeted: “We did it. In so many ways. We, the people.”
Actor Josh Gad, who starred in Frozen, tweeted: “In my lifetime, I’m not sure where the best Inauguration speech falls, by I am positive I just heard the most important inaugural speech of my lifetime just now.”