31st May 1921 might not stick out in your mind as a date of historical importance, but that's through no fault of your own.

In the most horrific example of racial violence in the history of America, the Tulsa Race Massacre was so heavily covered up and willingly written out of history that even 100 years later there are still questions that remain unanswered.

On Monday 30th May 1921, a black teenager got into the only lift in the Drexel Building to visit the restroom on the top floor. The 19-year-old shoeshine, Dick Rowland, entered the lift with the white attendant - 17-year-old Sarah Page. Witnesses heard what they believed to be a woman's scream, and then saw Rowland exit the building with some haste. A witness saw Sarah in a state of distress and, assuming that she had been assaulted by Rowland, called the police.

To this day we have no information about what happened in that elevator, but ideas have ranged from Rowland tripping and grabbing Page's arm or accidentally standing on her foot. So how did this brief encounter lead to a massacre?