Bio
Harvey Dietrich was a pioneering cattleman, visionary entrepreneur, and devoted supporter of the Arizona Jewish community. Known as both a rugged cattle rancher and a gracious gentleman, he built a life defined by hard work, philanthropy, and a deep commitment to improving the world around him.
Dietrich’s path to ranching began far from the open range. Born in Boston, he moved with his family to Los Angeles as a young teenager. At only fifteen, he went to work in a meat-packing plant, where his determination and instinct for business quickly set him apart. By nineteen, he had risen to the role of cattle buyer, launching a career that would eventually transform the beef industry.
In 1959, Dietrich moved to Phoenix and continued climbing through the cattle business. His entrepreneurial drive led him to help launch Sun Land Beef Co., a company that revolutionized beef processing and became one of the largest beef production operations in the western United States. After selling his stake in 1997, Dietrich shifted his full focus to ranching—an enterprise he had begun as a side venture two decades earlier. That small beginning grew into the 770,000-acre Diamond A Ranch in Seligman, now the largest cattle ranch in Arizona.
“He was basically a self-made man,” recalled Larry Bell, executive director of the Arizona Jewish Historical Society. “You could never go five or ten minutes without his cell phone ringing—something to do with cattle, feed prices, the fall roundup—he always had business going on.”
Dietrich was equally respected for his stance on natural beef production. He worked tirelessly to eliminate chemicals, artificial drugs, and GMOs from cattle feed, pushing the industry toward a healthier, safer, and more natural model. “We keep looking for a better way to make food safer, better, higher quality,” he said in a 2019 AZJHS video. “That’s a great mission. You help a lot of people.”
His work earned national recognition. In 2014, the Arizona National Livestock Show named him Arizona Pioneer Stockman, and in 2015, the National Cowboy & Western Heritage Museum awarded him the Chester A. Reynolds Award for unwavering commitment to Western principles.
Beyond ranching, Dietrich was a generous and quiet philanthropist. With his wife, Marnie, he supported organizations such as the Mayo Clinic Cancer Center, T-Gen Cancer Research Institute, the Jewish National Fund, Hillsdale College, the Phoenix Art Museum, and the Greater Phoenix Jewish Film Festival. He served on the boards of AZJHS and Kivel Campus of Care, and in 2019, he and Marnie received the Jerry Lewkowitz Heritage Award.
Friends remember him not only for his philanthropy but also for his humility. “He was a giving, generous guy,” said longtime friend Jerry Lewkowitz. At board meetings, Dietrich often arrived with lunch for everyone, without requesting recognition.
In his final years, Dietrich often spoke about the responsibility to improve lives and to stand against hate. “It’s what you leave in people’s hearts,” he said. “If you have that opportunity to change people’s lives, that’s extremely important.”
