The Rosebud-Treasure County Fair began in 1906, and with the exception of two years, has been summer's biggest celebration for thousands of residents of Rosebud County, Treasure County and the surrounding area. In 1934, the fair was canceled due to drought, which had led to an invasion of grasshoppers and crickets. German prisoners-of-war occupied the fairgrounds in 1945, so the fair was also canceled for that year. In 2020, due to the Covid-19 coronavirus pandemic, the fair was still held, but in a much-abbreviated format.  In the early days, the fair was held after harvest, in September. Later, it was moved to August and finally around 1990, to its current late-July dates, making it one of the earliest county fairs in Montana, but is also one of the longest running.