Carl (or Karl) Thomas Mozart was the second son, and the elder of the two surviving sons, of Wolfgang Amadeus Mozart and Constanze Weber. His young brother was Franz Xaver Wolfgang Mozart.
Karl was born in Vienna. His schooling, in Prague, was under Franz Xaver Niemetschek and František Xaver Dušek, and he became a gifted pianist. Before he finished his schooling, however, he left for Livorno in 1797 to begin his apprenticeship with a trading firm.
He planned to open a piano store in the following years, but the project failed for lack of funds. He moved to Milan in 1805 and studied music with Bonifazio Asioli, though he gave up his studies in 1810 to become an official in the service of the Austrian financial administration and the governmental accounting department in Milan. He also served as official translator for Italian for the Austrian Court Chamber. He owned a house in the village of Caversaccio in Valmorea, Province of Como; he appreciated the amenities of the place and the wholesomeness of the water. He bequeathed the house to the town, which is stated on a plaque dedicated to him. The Town Hall keeps a copy of the will.
He also frequently attended events related to his father until his death in Milan in 1858. Like his brother, he neither married nor had children, and the direct Mozart line thus died with him.
Alla memoria di
ultimo figlio del sommo musicista
funzionario del municipio di Milano
Vienna 1784 - Milano 1858
con lui si estinse la stirpe
ma non la gloria imperitura dell'illustre genitore
nel centenario della sua morte
l'associazione degli austriaci di Milano
-31 ottobre 1958
Gravesite Details Body lost; cenotaph at Milan Monumental Cemetery