The Art Deco 20th Century Theatre was built for William David Gross, who also owned the Coliseum Theatre in Juneau.

Around 1940, the Kimball organ from the Coliseum Theatre was moved into the 20th Century Theatre. A few years later, the Coliseum was destroyed by fire. The organ was moved to the State Office Building in 1976.

The 20th Century was twinned in the early 1980s by creating a second auditorium out of the balcony. The auditoriums were remodeled in 2004. Both auditoriums feature the original 1940 Simplex projectors.

Source: Cinema Treasures website

The Gross 20th Century Building contributes to the Juneau Downtown Historic District.