Martha Sotiriou was born in Athens, Greece. She began her musical studies at the age of 8 (guitar and theory of music). She received her diploma at the Athenaeum "Maria Callas" Conservatory in Athens with distinction, First Prize and Golden Metal Special Prize (class of Christina Giannakopoulou) and her Master in Opera at the Academy of Music "Carl Maria von Weber" in Dresden, Germany (class of KS Prof. Matthias Henneberg), where she studied from 2016 until 2018. She also attended the Art Song (Lieder) class of KS Olaf Bär in the same university.
She made her operatic debut at the age of 25 as Hänsel in E. Humperdinck's opera "Hansel und Gretel" in Athens. Other roles include "The Fox" in L. Janacek's "The Cunning Little Vixen", Maddalena in G. Verdi's "Rigoletto", Annio in W.A. Mozart's "La Clemenza di Tito", Princess Nicoletta in S. Prokofiev's "The Love for the three Oranges", the Third Lady in "Die Zauberflöte", Seconda Ancella in Cherubini's "Medea" (David McVicar's Metropolitan Opera staging), Kiki in the greek operetta "The Godson", The Psychiatrist in Geertje Boeden's musical comedy "Liebesgrüße aus Muskau", Ludmila/Mermaid/Fox in A. Baltas' children opera "Frikadela", Joana in the musical "Santa Maria, Insel wie aus Träumen geboren"as well as the Alto solo parts in Handel's "Messiah" and Mendelssohn's "Elijah". In 2023/24 she will debut the roles of Enrichetta di Francia in V. Bellini's "I Puritani", Tisbe in G. Rossini's "La Cenerentola" and Titika in N. Hadjapostolou's famous greek operetta "The Apaches of Athens".
As a soloist she has worked with the following opera houses and organisations: Theater Kiel, Kammeroper Schloss Rheinsberg, Theater Görlitz, Landesbühnen Sachsen, Greek National Opera, Eduard von Winterstein Theater, Schlossfestpielen Ettlingen, Luisenburg Festspiele, Olympia City Music Theatre "Maria Callas“, Staatsschauspiel Dresden, Junge Kammerphilarmonie Berlin, City of Athens Symphony Orchestra and Choir, Academic Choir and Orchestra of the University of Stuttgart and the Athens Megaron Concert Hall. She was for a short time extra choir member of the Greek National Opera and during the 2018/2019 season she worked as 2nd Alto at the State Choir of the Semperoper Dresden. During her first professional contracts she sang in Franco Fagioli's "Rossini" album (Deutsche Grammophon), as a member of the small vocal ensemble "Armonia Atenea Choir".
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She has worked with directors like Georg Quander, Barbara Beyer, Manuel Schöbel, Solvejg Bauer, Jonathon Loy, Dirk Schmeding, George Petrou, Anette Leistenschneider and has taken part in opera masterclasses of Siegfried Jerusalem, Michael Nagy, Tassis Christoyannis, Cheryl Studer, Christiane Iven, Aris Argiris, Dimitri Kavrakos, belcanto expert Peter Berne and Daphne Evangelatos, as well as in numerous concerts, with piano and orchestra accompaniment.
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She is a winner of the 2020 International Singing Competition of the Kammeroper Schloss Rheinsberg Festival. Thanks to her excellent performance at the competition, she received a full scholarship for the 12th Lotte Lehmann Summer Academy. She was a semifinalist of the Cesti Competition 2020.