Since his work is categorized as illustration and was most famously featured on the cover of the Saturday Evening Post, fine art critics were slow to acknowledge the importance of Norman Rockwell (1894-1978) as true artist, though his work was enormously popular during his lifetime and has endured as a crucial element in America's perception of itself in the 20th century. Through the Roaring Twenties, the Great Depression, World War II, the 1950s and 60s, Rockwell illustrations were a part of daily life, showing, as he once said, "the America I knew and observed to others who might not have noticed."