Gloria Coates (née Kannenberg; October 10, 1933[a] – August 19, 2023) was an American composer who lived in Munich from 1969 until her death.

Her First Symphony "Music on Open Strings" was played at the 1978 Warsaw Autumn and was the first composition by a woman in the musica viva series of Bayerischer Rundfunk.

[2] She met composer Alexander Tcherepnin in 1952, who encouraged her and gave her private lessons, and whose summer courses at the Salzburg Mozarteum she attended in 1962.

[4] Coates then studied at different universities and the Cooper Union Art School, achieving a bachelor's degree in drama and painting in 1963, and in composition and singing the same year.

She has great interest and significant participation in painting, architecture, theater, poetry, and singing—but it is through composing that she taps into a wellspring of abstracted emotionality that the others cannot reach.

Whatever the veiled expressions of her work may be, there is an undoubted emotional richness present, which if not concretely knowable is at least viscerally felt by the audience.

[9]Mark Swed wrote that "Coates is a master of microtones, of taking a listener to aural places you never knew could exist and finding the mystical spaces between tones.

"[10] Kyle Gann described in liner notes to one of her albums: Behind the variety of such techniques, behind even the varying deployment of similar structures, one hears Coates's constant aesthetic: her sense of each movement as a unified gesture, her almost post-minimalist unidirectionality.

[12] In her paintings, complementary colors such as red and green, yellow and blue, interact, in a manner of swirls of colours reminiscent of the style of Vincent van Gogh.

[13] Several of Coates' compositions were recorded,[13][14] by artists including the Kreutzer Quartet, the Stuttgarter Philharmoniker, Münchener Kammerorchester, and the Bavarian Radio Symphony Orchestra.