Francis I, just as his two great rivals – the Emperor Charles Quint and Henry VIII, was a true Renaissance’s Prince. Dubbed by Knight Bayard after his victory at Marignan in 1515, he was also a great protector of the Arts and Architecture as shown by major building works of Chambord or Fontainebleau. His reign saw the birth of Modern France by administrative reforms and the use of French as the official language of the administration with ordinance of Villers-Cotterêts in 1539.