The Tour de France was invented to sell newspapers.
In 1903 the sports paper "L'Auto" was locked in rivalry with "Le Vélo". Editor Henri Desgrange organised a cycling race around France: six stages, 2,428 kilometres, 60 starters, 21 finishers. Circulation soared. The yellow jersey arrived in 1919 and matched the colour of L'Auto's newsprint.
Useful: Many sporting events began as marketing and then became tradition.
Source: en.wikipedia.org