In 1966, the King of Norway made Nystedt a Knight of the Order of St. 164 A (2001), commissioned by the Ceciliaforeningen. 162 (2001), commissioned by the Augsburg College Choir and Reach Out For Peace for soprano, choir and orchestra, op. 159 (2000), featuring texts by Sophocles, Hippocrates and Plato The Word Became Flesh, op. 155 (1998), commissioned by the Oslo Philharmonic Ode til mennesket, op. Key Nystedt works include the symphony Apocalypsis Joannis for soloists, choir and orchestra, op. On the occasion of his 90th birthday in 2005, there were several concerts around the world held in his honour. It was also the first CD with a Norwegian composer nominated for a Grammy. This CD was nominated in two categories in the 2007 Grammy Awards and was the first Norwegian CD so nominated.
The choir Ensemble 96 published "Immortal Nystedt" in 2005.
He also founded and conducted the Schola Cantorum from 1964 to 1985. Nystedt founded and conducted the Norwegian Soloists' Choir from 1950 to 1990. He was the organist in the Torshov Church in Oslo from 1946 to 1982 and taught choir conducting at the University of Oslo from 1964 to 1985. Nystedt studied with Aaron Copland among others. Old church music, especially Palestrina and Gregorian chants, have had a major influence on his compositions. His major compositions for choir and vocal soloists are mainly based on texts from the Bible or sacred themes. Nystedt was born in Kristiania (now Oslo), Norway, and grew up in a Christian home where hymns and classical music were an important part of everyday life.