The Supreme Reign of the DSLR Began in 1999: How Did It Happen?

The millennium was yet to dawn, but 1999 saw Bill Clinton acquitted, the Columbine massacre, the world's population hit 6 billion, and "The Sopranos" debut. Lance Armstrong won his first Tour de France, the Euro came in to circulation, Napster was released along with Internet Explorer 5, and "The Phantom Menace" and "The Matrix" were first screened. But why did it also see the birth of the DSLR?