Emilie da Fonseca was born in
Copenhagen, Denmark. She was the daughter of
Portugal-born Abraham da Fonseca (1776–1849) and Marie Sofie Kiærskou (1784–1863). She and her sister
Ida Henriette da Fonseca (1802–1858) were students of
Giuseppe Siboni (1780–1839), choir master of the
Royal Danish Theatre Opera in
Copenhagen. She debuted in October 1827 as Susanna in
The Marriage of Figaro at the Copenhagen Opera, and was given a position there alongside her sister the same year. In 1831, she left Denmark and was given a position at the newly opened Christiania Public Theatre (
Christiania Offentlige Theater) in Christiania (now Oslo). In Norway, she became one of the most noted artists. She also performed as a
concert singer in the concerts arranged by the musical society, which performed many arias from famous operas in the Norwegian capital at this time.{{cite web|url= https://oslobyleksikon.no/index.php?title=Christiania_offentlige_Theater|title = Christiania offentlige Theater|website= Oslo Byleksikon She first married in 1839 to music teacher Ludvig Ernst Müller who died ca. 1840. After his death, she was married in 1841 to artist Ludvig Wilhelm Theodor Bratz (1811-1868).{{cite web|url= https://nkl.snl.no/Ludvig_Wilhelm_Theodor_Bratz|title = Ludvig Wilhelm Theodor Bratz ==References==