"From 1918 to present day, rodeo has changed," she wrote in 1999. "Cowboys and cowgirls now travel by airplane, but the spirit of rodeo prevails."
Here are some chronological highlights of the Black Hills Roundup that Kennedy shared during Western Horseman's recent visit to the historic Fourth of July celebration.
1919: Once again, Tipperary, the never-before-ridden horse raised in Harding County, South Dakota, ruled the rodeo. World champion bronc rider Leonard Stroud tried to tame the bronc, but as with previous riders' attempts, was unsuccessful.
1920: Chutes were built for rough-stock and used during the rodeo.
1923: The first carnival sideshow made its appearance.
1926: First sound system boomed over the crowd. Teddy Roosevelt's Roughriders also held a reunion during the rodeo.
1927: President Calvin Coolidge attended the rodeo and stayed the entire time.
1931: The Belle Fourche Cowboy Band made its debut at the rodeo. The musicians' red shirts, white chaps, cowboy boots and cowboy hats have become emblems of the rodeo.
1939: Brahma bull riding was introduced to the rodeo.
1942: In the dawn of World War II, fuel rationing and a lack of competitors due to overseas fighting, put a damper on the rodeo. That year, an event was staged for locals, but didn't match the roundup's usual caliber.
1956: Miss Rodeo South Dakota pageant added to the rodeo lineup.
1985: Yakima Canutt, the first cowboy to make a qualifying ride on Tipperary, returned to the rodeo as honorary parade marshal.
2004: Last year marked another history-making event when hometown rodeo hero Marvin Garrett scored a career-high, 90-point ride on Powder River Production's world-champion bucking horse Khadafy Skoal, also raised in South Dakota.