Thomas Hannah (1867–1935) was a Scottish-American architect based in Pittsburgh in the United States. He is credited with designing the Saint Nicholas Greek Orthodox Cathedral. He also designed the Western Theological Seminary in Pittsburgh. He also designed Midtown Towers, originally known as the Keenan Building and built in 1907. It was built for Colonel Thomas J. Keenan, owner and founder of the Penny Press, which became Pittsburgh Press. The building may have been modeled after the Spreckel Building/ Call Building (1898) of San Francisco. It is decorated with visages of 10 notables associated with Pittsburgh and Pennsylvania, including then-mayor George Guthrie and then-governor Edwin Stuart, in addition to George Washington and Teddy Roosevelt. The dome was once capped with the figure of an eagle in flight.
Hannah came to Pittsburgh in the late 1800s and began his career as a draftsman in the office of William Smith Fraser. When Fraser died in 1897, Hannah took over the firm with Fraser's nephew William F. Struthers to form Struthers & Hannah. The firm was credited with the design of the Andrew Carnegie Free Library (1901), a Carnegie library at 300 Beechwood Avenue in Carnegie, Pennsylvania. Plans for a Presbyterian church at Hamilton and Lang avenues, alterations to the Commercial National Bank Building at 316 Fourth Ave, brick and terracotta People's National Bank building At the firm, Hannah is credited with The First Congregational Church (1904) on Dithridge Street near Forbes, a sandstone-fronted gray brick building that eventually became the St. Nicholas Greek Orthodox Cathedral.
