This makes impeachment in the House official and becomes the third time in US history that a President has been impeached.
Chief Justice John Roberts and the senators who will serve as jurors were sworn in Thursday for the Trump impeachment trial, as the historic proceedings opened in the Senate with a mix of pageantry and partisan swipes.
"Senators, I attend the Senate in conformity with your notice for the purpose of joining with you for the trial of the president of the United States," Roberts said, before Iowa Sen. Chuck Grassley, the president pro tempore, administered the oath to him.
Roberts then immediately swore in the senators, who will act as the jury in the trial. And one-by-one, each senator took turns approaching the well of the Senate to sign an oath book.
After the swearing-in, Senate Majority Leader Mitch McConnell said the trial will continue at 1 p.m. EST on Tuesday.