In 1235 the young mums of Acoz already prayed to «little Saint Frégo» to protect their children from the ‘window’illness and other childhood diseases. The village had only a small population and the inhabitants could not plan a procession. Worship was therefore limited
to prayers in the chapel.
In 1866, a cholera epidemic spread terror in the village and its surroundings. That year, the Scieur, family who suffered badly, had erected a simple roadside chapel dedicated to the patron saint of the plague victims. In those days Acoz enjoyed great prosperity thanks to
its rolling mills, its blast furnaces, its sand quarries and its brewery. It was then decided to honour St. Roch and St. Frégo simultaneously. That is the origin of the military march dedicated to two saints, held on the Sunday following 15 August.