"I'm going to ask you to sing this last verse with me," Brooks said during the performance. "Not just the people here, but the people at home, at work as one. United."
Watch the inauguration of Joe Biden and Kamala Harris below.
The Country Music Hall of Fame member announced his big gig during a Monday morning (Jan. 18) press conference.
Brooks joined performers Lady Gaga and Jennifer Lopez in welcoming Democrats Biden and Vice President Kamala Harris to the White House.
"This is a great day in our household. This is not a political statement. This is a statement of unity," Brooks announced on Martin Luther King Jr. Day.
Brooks is no stranger to inauguration invites. He performed at Barack Obama's inauguration in 2009. Four years ago, he declined an invitation to President Donald Trump's big day because of a conflicting tour stop in Cincinnati.
Despite his friendship with Jimmy Carter, Brooks doesn't see himself as favoring Democrats over Republicans. That's partly why he dismisses questions about potentially becoming America's next celebrity president.
"Trust me, no one would know which way to go with me because I am so both," Brooks told Billboard. "I really am 'Let's love one another, but don't forget we're the defender of freedom all around the world, so let's beef up.' People don't think you can do both. And that's right down my alley. That's why you can have 'We Shall Be Free' and 'American Honky Tonk Bar Association' at the same concert. Let's love one another and let's pull our own weight."
Brooks not being able to win when it comes to politics was driven home in Feb. 2020 by confusion over whether or not a Detroit Lions jersey representing fellow Oklahoma State University grad and all-time great running back Barry Sanders was an endorsement of Bernie Sanders.