The Keith Theater opened on January 27, 1908, on Preble Street in Portland, Maine. Its owner, B.F. Keith, also owned theaters in Boston, Philadelphia, New York, Providence, Cleveland, and Columbus. Initially seating 1,600 people, the theater presented vaudeville, stage shows, and occasional movies. By the 1920s, it had switched to showing films exclusively. The theater was considered very modern for its time, with elaborate decorations and furniture.

In 1939, the theater changed ownership and was renamed the Civic Theatre on October 29. By 1950, it was operated by the Zeitz Bros. Circuit. The Civic Theatre continued to operate until 1963, after which it was closed. In 1965, the building was demolished to make way for a parking lot. 

Although the Civic Theatre itself was demolished, the Civic Arcade, which served as the lobby to what is now the Casco Bank Building and as an entrance to the theater, still exists. In the 1950s and 1960s, the arcade housed two banks, a coffee shop, a religious articles store, a radio station and a pet store. It also had a flooring and carpet shop, and when the Civic Theatre closed in 1963, the arcade became a storage site for rolls of linoleum and carpeting for the shop. There were rumors that the arcade entrance would be restored a few years ago, but nothing came of it.