Second Empire is an architectural style, most popular in the latter half of the 19th century and early years of the 20th century. It was so named for the architectural elements in vogue during the era of the Second French Empire. As the Second Empire style evolved from its 17th-century Renaissance foundations, it acquired a mix of earlier European styles, most notably the Baroque, often combined with mansard roofs and/or low, square based domes.
The style quickly spread and evolved as Baroque Revival architecture throughout Europe and across the Atlantic. Its suitability for super-scaling allowed it to be widely used in the design of municipal and corporate buildings. In the United States, where one of the leading architects working in the style was Alfred B. Mullett, buildings in the style were often closer to their 17th-century roots than examples of the style found in Europe.