Ralph Spencer Twitchell (July 27, 1890 – January 30, 1978) was one of the founding members of the Sarasota School of Architecture. He is considered the father of the group of modernist architecture practitioners, that includes Paul Rudolph and Jack West, and other modernist architects who were active in the Sarasota area in the 1950s and 1960s like Ralph and William Zimmerman, Gene Leedy, Mark Hampton, Edward "Tim" Seibert, Victor Lundy, William Rupp, Bert Brosmith, Frank Folsom Smith, James Holiday, Joseph Farrell and Carl Abbott. He bridged the more traditional architecture of his early work in Florida during the 1920s with his modernist designs that began in the 1940s.
Twitchell was born in Mansfield, Ohio, but the family moved to Winter Park, Florida in 1906 after the untimely death of his father. Upon moving, Twitchell enrolled in Rollins College, but transferred to McGill University, Montreal, in 1910 to study architecture. In 1912, Twitchell transferred schools again, to Columbia University. After his 1917-19 World War I military service, Twitchell graduated from Columbia with a Bachelor of Arts degree in architecture in 1920 and a Masters in Architecture in 1921.
Twitchell first came to Sarasota as the representative of New York architect Dwight James Baum to manage the final stages of the construction of John Ringling's Cà d'Zan, a Venetian-style mansion on the Sarasota Bay. He also worked with Baum on the Sarasota County Courthouse. Following this, Twitchell purchased 13 lots in the Ravellan Gardens bayside neighborhood of Sarasota and designed Mediterranean architecture homes on these lots. Lauded in the press, the homes were financially problematic as the Florida real estate bubble of the 1920s had collapsed. Some of the homes survive and have been included on the National Register of Historic Places.