Latvian composer and pianist Pēteris Plakidis was born in Riga on 4 March 1947. He studied at the Emīls Dārziņš College of Music and then at Jāzeps Vītols State Conservatory.
He was musical director of Latvian National Theatre from 1969 until 1974. From 1975 he taught composition at the Latvian Academy of Music, and from 1991 he was professor of composition.
His Music for Piano, String Orchestra and Timpani won him a diploma at the All-Union Young Composers' Competition in 1969, and his Variations for Orchestra won the Latvian Great Music Award in 1996.
He was commissioned to write music for orchestral works for the Latvian National Symphony Orchestra.
Pēteris Plakidis died on 8 August 2017, aged seventy.