The history of the outlaw motorcycle movement has been distorted by myth, legend and media hype but some books like Sonny Barger's " HELL'S ANGEL: The life and times of Sonny Barger " and Hunter S. Thompsons' " HELL'S ANGELS - A STRANGE AND TERRIBLE SAGA " throw some light on a ever vanishing glimmer of fact. However other events surely contributed to the outlaw movement.

The History of Sturgis.

The story goes something like this. Back in the thirties, J.C. Hoel and some riding buddies formed a motorcycle club called the Jackpine Gypsies. The purpose of the club was to hold events and racing.
One version of the story has a rider killing a pig on one of their outings. When the group went to the farmer to compensate him for the animal, the rancher declines payment and gives the pig to the club. The club has a pig roast and thus the first Sturgis.
Another (and more historically correct) version of the story has Clarence J. C. "Pappy" Hoel, who was also a business man and owner of the local Indian dealership at a time when the Harley-Davidson and Indians wars were being waged, decided to hold a meet on a new half mile oval dirt track complete with stunt shows to compliment the racing.
This first Sturgis was held on August 14, 1938. The first Sturgis Motorcycle Rally had a total of nine racers competing for a $500 purse on the new half mile oval dirt track Stunt riding were an integral part of the event.
This event became known as the Black Hills Motorcycle Classic. During the 1940s, the event became popular and attracted more and more people. The event was cancelled during World War II but by 1945 was back.
Sometime during the disillusionment that followed WWII, another biker event began. This was held in the small town of Deadwood, about 20 miles away. This was an "outlaw" biker rally and the two events were separate.
The sixties saw an increase in traffic to both sites, and attendees at the AMA rally and the "outlaw" rally began visiting each other. In 1965 about 1,000 bikers camped out in the City Park (later closed).
By 1976, Sturgis had become the center of activity for a single rally. This was a real bikers event, known mostly to hard core riders. The 1980s rolled in and Sturgis began to change. Press coverage of the event touted Sturgis as a "down-to-earth unspoiled Harley biker outlaw idyll". Harleys became "in" and life in unspoiled nature also became "in". Sturgis offered all of this and more.
At this point, about 30,000 people were attending the event. In 1990 an estimated 400,000 bikers descended on Sturgis to celebrate its 50th anniversary. And 1990 is critical in that Sturgis itself underwent a transformations.
The Black Hills Motor Classic was replaced by the Sturgis Rally and Races. Commercial marketing of the event exploded, and the event is now widely regarded as the largest motocycle event in the world. The National Motorcycle Museum was created and corporate sponsorship of the event took off.
This year is the 60th anniversary and 600,000 are expected to attend. And racing is still an integral part of this event. you can now see dragsters, hillclimbs and motocross as well as oval track racing. And Sturgis is no longer considered a rally for the "outlaw" clubs. It has become a regional event.
By this, I mean Rapid City, towns in the Black Hills and other areas surrounding Sturgis are now part of the event. Events have been added progressively throughout the years, and the schedule of activities is phenomenal with over 124 events being held over ten wild days of motorcycles.

However we also have the 1947 Hollister incident.

A band of bikers rode into Hollister, CA. on July 4, 1947 for a 3-day rally. Some drunkenness occurred and the press made a sensational story out of it that appeared in Life magazine. Most of the biker movies have perpetuated the Hollister image that appeared in Life. The movie, the Wild One, starring Marlon Brando was based on this incident. Ironically in the Wild One Marlon Brando ( the goody ) rode a Triumph and Lee Marvin ( the baddy ) rode a Harley Davidson....an omen of things to come ? The movie was banned in the UK for many years in fear that the same may happen there. Even today, motorcyclists are still viewed in the light of Hollister.

Furthermore we have the story that the origin of Hell's Angels was a club comprised of veterans and named after the Hell's Angels B-17 bomber group of World War II. A myth strongly denied by the Hell's Angels, refer Hell's Angels World.

I'm sure the true history is intermingled somewhere in this page.