Γεννημένος στην Στοκχόλμη της Σουηδίας το 1925, εγινε γνωστός στο ευρύ κοινό οταν τον ανακάλυψε ο Walter Legge:
Walter Legge, EMI’s legendary record impresario, and his wife, Elisabeth Schwarzkopf, were in town and demanded to hear the new tenor everyone was raving about. After a short audition, Legge immediately fired off cables to conductor Herbert von Karajan and Antonio Ghiringhelli, the intendant of La Scala: “Just heard the greatest Mozart singer in my life: his name is Nicolai Gedda.”
What happened next would probably leave any young singer breathless. Gedda was instantly cast as Dimitri in EMI’s splashy new recording of Boris Godunov, starring Boris Christoff (“that Boris recording opened the doors of the world to me,” Gedda once remarked), and he made a La Scala debut as Don Ottavio in Don Giovanni under Karajan’s baton. Gedda suddenly had invitations to sing everywhere—Faust and Weber's Oberon in Paris, the Duke of Mantua at Covent Garden and dozens of other requests from Rome, Vienna, Salzburg, Berlin, Munich and Tokyo.