Maria Theresa Mathilda Tilly Fleischmann (2 April 1882 – 17 October 1967) was an Irish pianist, organist, pedagogue and writer of German descent.
Fleischmann was born Maria Theresa Mathilda Swertz on 2 April 1882 in Cork,Ireland, the second of nine children born to her German parents, Hans Conrad Swertz, a music teacher from Camperbruch, today Kamp-Lintfort and Walburga Rössler of Dachau. She was educated at St Angela's College in Cork; she studied the piano at the Cork Municipal School of Music and the organ with her father, who was organist and choirmaster in the Catholic Cathedral of St Mary and St Anne.
In September 1901 her father sent her to study in Munich at the Royal Academy of Music (Königliche Akademie der Tonkunst). Women had been admitted to the Academy since 1890, but until 1918 were taught separately. Tilly studied the organ with Josef Becht, and the piano with Bernhard Stavenhagen, Liszt's last pupil. When he left the Academy in 1904, she studied with Berthold Kellermann, also a pupil and close associate of Liszt. She graduated in June 1905 with best grades, having taken her final organ examinations in June 1904. From the second semester of her studies, she was invited to perform at all the public Academy concerts; in her final semester she played the Schumann Piano Concerto with the Academy Orchestra conducted by Felix Mottl.
In September 1905 she married Aloys Fleischmann of Dachau, who had also studied music at the Academy in Munich, taking composition with Josef Rheinberger, and was now organist in the parish church of his native town.
A year after her marriage, she was called back to Cork: her father had left Ireland to take up a post in Philadelphia; all eight brothers and sisters were still either at school or college, and she was the only one in a position to earn her living. She persuaded her husband to come to Cork with her to support the family; he was appointed to her father's former post at the cathedral. The Fleischmanns had not intended to settle in Ireland for good. In 1909 they decided that Tilly should spend some months in Munich, studying with her former professor, giving a concert and establishing contacts in the hope of their being able to return. She became pregnant three months before her departure, but they decided to carry out the plan nonetheless. Their only son Aloys was born in Munich on 13 April 1910; in July she returned to Cork with the baby. They gradually adapted to life in the city, finding many good friends among people interested in the arts; she gave recitals and taught the piano; her husband gave choral recitals in the city and composed for both his secular and church choirs.