Carl Czerny
Horszowski was born in Lwów (Lemberg), Austria-Hungary (now Ukraine) and was initially taught by his mother, a pupil of Karol Mikuli (himself a pupil of Frédéric Chopin). He became a pupil of Theodor Leschetizky in Vienna at the age of seven; Leschetizky had studied with Beethoven's pupil Carl Czerny. Leschetizky's sister-in-law, Angele Potocka, referred to Horszowski as "a wunderkind of high order".