High Quality Content by WIKIPEDIA articles! The Youth`s Companion Building is a historic building at 209 Columbus Avenue in Boston, Massachusetts. The building is also known as the Pledge of Allegiance Building because the Pledge of Allegiance was written and published there. The building originally had the address 201 Columbus Avenue and also has the address 142 Berkeley Street. It was built in 1892 and added to the National Register of Historic Places in 1974.