George B. Post's design for the Capitol combined novel structural approaches with traditional influences.

In the late 19th and early 20th centuries, Post designed buildings that pushed boundaries of height and explored new ideas about the very ways in which structures can support themselves. By employing novel design and engineering approaches that used steel and wrought-iron frames to support buildings' exterior walls, he made it easier to the buildings to have more open interior spaces, and in some cases, more windows. Wisconsin's Capitol was a late-career highlight for Post.

The structural ideas George B. Post used in early skyscrapers would later play a role in his design for the Wisconsin State Capitol. Post's major architectural accomplishments ranged from the New York Stock Exchange building to a massive structure at the World's Columbian Exposition in Chicago in 1893. Quagliana explained that surveying Post's career reveals how the architect developed and sometimes wrestled with his ideas about how tall buildings should look and function, and how those innovations influenced the Wisconsin Capitol's design alongside its more traditional inspirations.

Post was personally quite involved in the building's construction, making at least 20 train journeys from New York to Madison, which would have been pretty taxing for a man in his late 60s and early 70s. After Post died, both of his sons, who were architects and joined their father's firm in 1901, would go on to supervise the rest of the construction.
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