Born in Langres in Champagne-Ardenne William Dongois studied trumpet in Rheims and in Paris. He taught the instrument parallel to orchestral activity both at the Academy and at the Grand Théâtre in Rheims. As a member of the copper quintet of Champagne Ardenne he took part to numerous concerts and came to develop a passion for the musical repertoire of the XVIe and XVIIe centuries. During this time, he deepened his knowledge of musical language while studying with Olivier Trachier. He gained diplomas in harmony, ‘fugue' and counterpoint which, combined with his skill on trumpet and his love for the early repertoire naturally led him to master the cornetto à bouquin. He received his instruction on cornett from Jean-Pierre Canihac as a soloist and Jordi Savall as an ensemble musician.
Eventually, William Dongois ceased his career on trumpet, deciding instead to dedicate himself to the music of the XVIe to the XVIIIe centuries, without neglecting middle-aged repertoire, through diverse training courses on Gregorian and middle-aged counterpoint. He pursued his education at the Schola Cantorum Basiliensis with Bruce Dickey until 1992. From that period onwards, he has played and recorded with numerous Ensembles: Hespérion XX, Les Sacqueboutiers de Toulouse, le Concerto Palatino, Tragicomedia, Taverner's Players, Gabrieli's Players, Elyma, Musica Fiata, and under the direction of Michel Corboz, Joshua Rifkin and Philippe Herreweghe.
William Dongois played with the Ensemble la Fenice from its creation until 1993 during which time he won first prize in competitions at Bruges (1991) and Malmö (1992). He plays regularly with the Concerto Vocale of René Jacobs and other Ensembles including Weser Renaissance Bremen, Le Poème Harmonique and la Capella de la Torre. He has also played with the Ensemble Anthonello of Tokyo and Les Boréades of Montréal.
William Dongois has earned both a diploma of teaching and a Certificate of Competence for ancient instruments and teaches cornett and improvisation in numerous training courses and master classes throughout France, music high schools in Germany and as well as in Austria. He is professor of cornett at the Ancient Music Centre in Geneva.