Horace Jackson's life was deeply rooted in the vibrant city of Los Angeles, California, where he resided in the charming neighborhood of Bellaire with his loving wife, Gertrude. Born in the historic city of East St. Louis, Illinois, Horace was the son of Harry S. Jackson and Lena Atherton Jackson. He was blessed with a sibling, Helen Jackson, who would later become the wife of Leo E Mumford Sr. of Burbank. Tragedy struck when Horace's father, Harry, passed away in 1903, leaving behind a young Horace, Helen, and their mother, Lena. In the early 1910s, Lena made the bold decision to relocate her family to the City of Angels, settling in the Boyle Heights neighborhood, where she would purchase a home sometime in the 1910s.
As Horace grew older, he pursued a career in architecture, listing himself as an architect in the 1920 Los Angeles census. Unfortunately, his life was cut short in 1952 when he met an untimely death in an auto accident. His passing left behind his devoted wife, Gertrude Jackson, his mother, Lena Jackson, and his nephew, Leo Edward Mumford Jr. Additionally, he was survived by Leo's three children with Joy Bunnell Mumford: Joy Helen Mumford, Leona Margaret Mumford, and Leo E Mumford III.