The Marciano brothers were born in Morocco, and come from the village of Debdou in the eastern region of the country. Their family then moved to France, on the Côte d'Azur. They grow up in Marseille where they work in fashion. After the election of the Socialist François Mitterrand as President of the Republic in 1981, they decided to leave France and leave for Los Angeles in order to make jeans and found a brand. At that time, the American denim fabric went out of fashion. To launch their business, the Marciano brothers see the opportunity to associate it with the European style.

While he did not speak a word of English, Georges Marciano observes a billboard "Guess where's the best Hamburger? Big Boy "and decides to rename the company" Guess? ".