WASHINGTON—Former vice presidential candidate Paul Ryan has been chosen as the new speaker of the House.

The House voted Thursday morning to confirm Ryan. The Wisconsin Republican has been in the House since 1999 and was Mitt Romney's running mate in 2012.

At the age of 45, Ryan is the youngest House Speaker in more than 100 years.

John Boehner opened the historic House session. Boehner, who’s stepping down after five years as House speaker, gave farewell remarks on the House floor. He paid tribute to his colleagues, constituents, staff and his earliest campaign volunteers.

"That includes a student at Miami University in Oxford, Ohio in 1990 who was putting up campaign signs for me. His name was Paul Ryan," said Boehner.

In his victory speech, Ryan thanked John Boehner and called for  a new way of doing business  in the House  of Representatives.

Ryan is expected to push for unity in the Republican party.