Gustave Caillois was born on 15 December, 1874, in Paris. From the mid-1890s he took part in bicycle races using the pseudonym Siolliac (his name backwards). Then he upgraded to motorcycles – in 1899, he was seen at the Paris-Bordeaux race with a motorbike.
He soon became interested in automobiles and worked and raced first for Peugeot then Serpollet. In 1904, he joined the Brasier company. In 1905, he finished second in the elimination race for the Gordon Bennett Cup and finished a strong fourth in the final. A year later he was in America for the Vanderbuilt Cup but could not finish the Elimination Trial. Afterwards, he raced Darracq, Renault and finally Sunbeam. He retired from racing in 1913 and died in France on 13 February, 1958.