| John of Austria | |
|---|---|
 Don Juan de Austria, oil in canvas of 2nd half of the 16th century, probably by Juan Pantoja de la Cruz, in the Museo del Prado, Madrid | |
| Governor of the Spanish Netherlands | |
| In office | 1576–1578 |
| Predecessor | Luis de Requesens y Zúñiga |
| Successor | Alexander Farnese, Duke of Parma |
| Monarch | Philip II of Spain |
| Vicar of Spanish Italy (extraordinary position) | |
| In office | c. 1575 |
| Predecessor | Office established |
| Successor | Office dissolved |
| Monarch | Philip II of Spain |
| Born | 24 February 1547 Regensburg, Holy Roman Empire |
| Died | 1 October 1578 (aged 31) Bouge, near Namur, Spanish Netherlands (present-day Belgium) |
| Burial | 24 May 1579 |
| Issue | See detail |
| House | Habsburg |
| Father | Charles V, Holy Roman Emperor |
| Mother | Barbara Blomberg |
| Religion | Roman Catholicism |
| Signature |  |
| Military service | |
| Allegiance |
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| Branch/service | |
| Years of service | 1568–1578 |
| Rank |
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| Commands |
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| Battles/wars | See list |
John of Austria (German: Johann von Österreich, Spanish: Juan de Austria; 24 February 1547 – 1 October 1578) was the illegitimate son of Charles V, Holy Roman Emperor. Charles V met his son only once, recognizing him in a codicil to his will. John became a military leader in the service of his half-brother, King Philip II of Spain, Charles V's heir, and was addressed to as a Don. He is best known for his role as the admiral of the Holy League fleet at the Battle of Lepanto and as Governor of the Spanish Netherlands.