Final answer:
Bob Ross's background before fame includes his service as a first sergeant in the United States Air Force, where he was stationed in Alaska and developed his signature quick-painting technique.
Step-by-step explanation:
Before Bob Ross became a famous television personality and painter, he served in the United States Air Force. He developed his quick painting technique during his lunch breaks while stationed in Alaska, which later became a hallmark of his PBS show, The Joy of Painting. Ross's position as a first sergeant at Eielson Air Force Base in Alaska, where he first saw the snow and mountains that would later become recurrent themes in his artwork, greatly influenced his painting style. His military background is less well-known compared to his calm and nurturing demeanor on television, where he became famous for his gentle guidance and encouraging words to aspiring artists.