Monica Sinclair (23 March 1925 – 7 May 2002) was a British operatic contralto, who sang many roles with the Royal Opera, Covent Garden during the 1950s and 1960s, and appeared on stage and in recordings with Dame Joan Sutherland, Luciano Pavarotti, Maria Callas, Sir Thomas Beecham, Sir Malcolm Sargent and many others.
Her early Covent Garden roles included Maddalena (Rigoletto), Mrs Sedley (Peter Grimes), Feodor (Boris Godunov), Rosette (Manon), Flosshilde (Das Rheingold), Siegrune (Die Walküre), Azucena (Il trovatore), Pauline (The Queen of Spades), Mercedes (Carmen) and the Voice of Antonia's Mother (The Tales of Hoffmann).
[1] She made her Glyndebourne debut in 1954 in the comic role of Ragonde in the first British performance of Rossini's Le comte Ory.
There she also sang Berta (The Barber of Seville), Marcellina (The Marriage of Figaro), Dryade (Ariadne auf Naxos), and Queen Henrietta (I puritani, with Dame Joan Sutherland).
[2] Returning to Covent Garden in 1959/60, Sinclair added some new roles to her repertoire – Annina (Der Rosenkavalier, in Georg Solti's Covent Garden début, with Dame Elisabeth Schwarzkopf and Sena Jurinac), Bradamante (Alcina, directed and designed by Franco Zeffirelli, with Dame Joan Sutherland in the title role), Theodosia (Die schweigsame Frau), the Old Prioress (Dialogues des Carmélites), Marfa (Khovanshchina), Emilia (Otello) and the Marquise de Birkenfeld (La fille du régiment, with Sutherland and Luciano Pavarotti).