Born in Paris on February 23, 1896, Sarah Fischer came to Canada in 1909 with her mother Dora and sister to live with her father, Jacob Fischer, a hat manufacturer who had immigrated earlier. While still in her early teens, she worked as an operator for the Bell Telephone Company in Montréal. Fischer worked during the day, and in the evenings she studied solfège with Professor Jacques Goulet. She progressed well in her studies and in 1917, began voice lessons with Céline Marier, a Canadian singer who had studied in Paris with Romain Bussine. In the same year, she received a silver medal for her studies in solfège, and received a diploma from l'Académie de musique du Québec.
Fischer's most significant achievement in 1917 was winning the prestigious Strathcona Scholarship (also known as the McGill Scholarship), which provided funds for three years' tuition at the Royal College of Music (RCM) in London plus a grant of fifty guineas (about $120 CA) a year. Founded by Lord Strathcona (originally Donald Smith), famous for building Canada's first transcontinental railway and for his generous support of the arts, the Strathcona Scholarship program assisted the careers of numerous prestigious Canadian artists such as sopranos Pauline Donalda, Beatrice La Palme and Éva Gauthier.
Fischer performed selections from Hamlet for the competition, and was chosen out of 17 competitors. She recalled the day of the competition in an interview: "I worked all day at the switchboard before I sang for the scholarship committee. It was late in the afternoon and I was the last contestant. I didn't think I had a chance" (Sarah Fischer Archives, MG30 D207, vol. 63).
Fischer could not take advantage of the scholarship immediately because passports were not issued to women during the First World War. Fortunately, she had numerous opportunities to perform in Montréal, and sang with l'Association d'art lyrique where she studied drama with stage directors Albert Roberval and his wife Jeanne Maubourg.
On Nov 19, 1918 she made her operatic debut in Montréal as Micaëla in Bizet's Carmen at the Monument-National, and was described as "stunning … full of grace and bloom of youth" (Lamontagne, 1918). She continued performing in both Montréal and Québec, adding to her repertoire the roles of Colette in Messager's La basoche, Philine in Mignon, and in 1919, the leading role in Délibes' Lakmé.
In 1919, Fischer travelled to New York and made eight recordings on the Pathé label. The recordings included arias from Lakmé and Carmen, "Solvejg's Song" by Henzen and "Quand tu pleureras" by Marcel Chrétien.
By 1919, conditions in England were peaceful enough for Fischer to secure a passport and set sail for the RCM. Soon after her arrival, she called on Canadian opera star Emma Albani, who had settled in London, and a lifelong friendship ensued. Albani often attended Fischer's performances with her husband Ernest Gye and with Fischer's father when he visited her in England.
Fischer also sang in Albani's salon at 61 Tregunter Road, in Earl's Court, where Albani frequently entertained distinguished musicians. Fischer recalled their relationship in an interview: "Emma Albani was a great friend of mine. She was not my original teacher, I studied with her later. But, when I arrived in London with my Strathcona scholarship I didn't know what to do next. I knew her reputation, so I went to her for advice and she became my friend. She told me that (Cecilia M.) Hutchinson at the Royal College of Music was the person who could best bring out the qualities of my voice" (Heller, [n.p.]).