Henderson and his family disliked the weather of Ohio so while Gloria was visiting family in California, Henderson visited Denver, Colorado. In Colorado, Henderson interviewed with several architectural firms like Fisher and Davis, Eugene Sternberg, and Casper Hegner. On October 7th, 1959, with encouragement from Hegner, Henderson transferred his architectural license and became the first Black architect in Colorado.

Once Henderson and his family had moved to Colorado, they found themselves in segregated neighborhoods of Denver. Limited on where to buy a home given Denver’s racially discriminatory real estate practices, Henderson decided to build his own and bought one of the last available plots in the Skyland neighborhood. Located on the north side of Twenty-sixth Avenue, the Henderson House sits along what was once the line of de facto segregation in east Denver; today it’s the neighborhood’s first landmark.

This first year in Colorado, Henderson worked for Fisher and Davis while they collaborated with James Sudler Associates on the Federal Building and Courthouse (renamed the Byron G. Rogers Federal Building and U.S. Courthouse in 1984). Henderson continued his career with several other prominent Denver architectural firms in the 1960s including Earl C Morris, and designed schools under Wheeler and Lewis. 

Henderson only stayed with Wheeler and Lewis for a short period before leaving for James Sudler Associates. Under Sudler, Henderson worked on the drawings for the United Bank of Denver and a housing project for the Colorado School of Mines. The last firm Henderson worked with in his career was Hornbein and White. 

After years of architectural firm employment, Henderson transitioned to designing residential homes and a few commercial buildings’ alterations. Henderson’s residential designs spread throughout the Denver Metro area and include a 4000 sq. ft. home for Carlotta Walls LaNier, one of the Little Rock Nine. An active community member, Henderson and his wife owned and operated The African and American Trading Company, which sold African American art and furniture. Henderson also attended mass every Sunday at Denver’s St. Ignatius Loyola Church where he was the head usher until his mid-90s.

John R. Henderson passed away on June 29th, 2018. Later, Lynn B. Henderson, John Henderson’s son, donated his father’s collection to History Colorado in October 2019. The collection includes original drawings, sketches, and blueprints for commercial and residential buildings from 1951 through 1998, though most are from 1960-1988. 

How can witnessing John R. Henderson's success despite political and social adversity inspire or inform others?

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