Theodor Alexander Josef Wiederspahn (February 19, 1878 – November 12, 1952), also known as Theo Wiederspahn, was a German Brazilian architect. He designed many buildings in Southern Brazil, specially in Porto Alegre city. Other locations include Novo Hamburgo and Cruz Alta.

Born in Wiesbaden, having finished his studies in 1894, Theo Wiederspahn immigrated to Brazil in 1908. He intended to work for “Viação Férrea do Rio Grande do Sul”, a railroad state-owned company, but it never happened because of contract problems. Wiederspahn then started working as an architect for Rudolph Ahrons's engineering firm in Porto Alegre. Together they revolutionized the urban landscape of the city, and many of his works became part of its artistic cultural heritage.

Wiederspahn’s architectural approach was marked by eclecticism, skillfully merging various historical styles to create distinctive, ornate structures. Some of his most recognized works include the Ely Building, the Rio Grande do Sul Museum of Art, and the Casa de Cultura Mario Quintana, initially known as the Hotel Majestic. The Hotel Majestic, one of Wiederspahn’s designs, was the first large structure in Porto Alegre to employ reinforced concrete and featured unique architectural elements, such as suspended walkways over public streets.^[1]

Throughout his career, Wiederspahn encountered various challenges, such as the closure of Ahrons’s firm in 1915 and the socio-political ramifications of World War I. Despite these difficulties, he continued to enrich the architectural landscape of Porto Alegre and other cities in Rio Grande do Sul, contributing a wide array of structures, from educational and religious buildings to residential and commercial spaces. His work has been showcased in exhibitions and explored in scholarly research, underlining his lasting influence on Brazilian architecture.^[1]

• Theodor Wiederspahn - Biography (in Portuguese)