Biography
Costeley's output centered chiefly on the chanson, yet he stands out as likely the earliest composer to attach the word “air” to pieces in that form. The designation referred to melodic ideas that recurred from one stanza to the next of the poems he set, altered only slightly while the underlying rhythmic framework stayed fixed. He knew the work of Arcadelt, Sandrin, Ronsard, Belleau, Baif, and Maillard and may have exchanged influences with each of them. Service at the Italian court placed him in the household of Queen Mother Catherine de'Medici. Within his own writing Costeley experimented with microtones, clusters of accidentals, vertical harmonies rather than contrapuntal textures, and both augmented and diminished intervals. Keyboard music formed his principal domain, yet almost no French examples from the period survive; as a result, the single piece of his that remains occupies a position of special importance.