The building was constructed in four phases, beginning with the north and south portions of the three-story square base, built from 1922 to 1924. This square outer edge of the building was filled in with + shaped wings, leaving four square interior courtyards. Three of the four wings of the + were built from 1925 to 1928. The tower was added in the middle of the + from 1928 to 1930. The fourth arm of the + finished the building in 1932.
Names of all ninety-three counties in Nebraska are inscribed around the top of the building's base. Above the names, twenty-one panels represent the creation of law. Interestingly, the building was originally going to house a law library whose book stacks would be located in the tower. This did not occur, however, and the tower houses offices. Eight sculptures around the base of the tower, visible from the courtyard, represent the ideals of culture.
The interior contains three major spaces - the Vestibule, Great Hall, and Rotunda. The Vestibule's dome features a sun motif in a medallion; four 25-foot columns of red marble with a bull motif in the capitals support the vaulting. A series of bronze busts of famous Nebraskans form the Nebraska Hall of Fame in the Great Hall. Eight winged virtues form a celestial rose in the dome of the Rotunda. A series of designs in the mosaic tile floor of the Great Hall and Rotunda are themed the Procession of Life, from fossils to animals, vegetables, and humans.
A number of hand-painted murals decorate the building's interior. Two were finished in the early years of the building, but the program was suspended when funds ran out. The mural project was revived in the 1950s and 1960s. Another series of murals was finished in 1996, in the Memorial Chamber on the 14th floor. The fourteenth floor is the highest publicly- accessible floor and offers observation decks for spectacular views for miles from 245 feet above the ground. The fifteenth floor is the top of the tower. The Nebraska State Capitol was the tallest building in Nebraska until being surpassed by buildings in Omaha in 1969 and in 2002.