William Knudsen (1859-1914) was born in Norway and came to America in 1882. He worked as a carpenter on the Capitol and his tool box and tools, donated by his descendants, are now in the collection of the Minnesota Historical Society. He and his wife, Bertha, raised a large family in St. Paul and died there in 1914 at the age of 54.

Knudsen joined Carpenters Local 87 on Nov. 8, 1898 right at the beginning of their huge membership surge. In the City Directories, he always listed St. Paul Building Co. as his employer. Perhaps the company farmed him out to the Butlers for a time or maybe the Butlers subcontracted out some of the carpentry.