The article sheds new light on the life of Antun Rozanović (Antonio Rosaneo/Roseneo), a native of Korčula, in Dalmatia, who played a key role in the successful defense of his city from the Ottoman attack launched in the summer of 1571. Rozanović wrote a Latin account of the event that is at once a work of historiography, a literary narrative, and a memoir; it circulated in manuscript until its publication in Croatian translation in the second half of the nineteenth century. Archival sources in Croatia and abroad enable us to reconstruct Rozanović's biography with considerable certainty and to significantly advance our knowledge of Rozanović's travels and activities both before and after the dramatic events of 1571. Born in Korčula in 1524, Rozanović went to study law at the University of Padua around 1542, graduating in 1549. As a senior student there, for a while he taught ars notaria (1547-1548). Having returned to Korčula as a doctor, in the mid 1550s Rozanović aspired in vain to become a canon of the Korčula cathedral chapter; letters sent by the Ragusan archbishop Lodovico Beccadelli to his Italian friends reveal details of Rozanović's aspirations. Beccadelli was acquainted with Ivan Krstitelj Rozanović, Antun's father, and secured a post for Antun in his own curia in Dubrovnik (1557-1558). In late 1559 Rozanović traveled to Rome, where in the following year he became e member of the Confraternity of St. Jerome, the patron saint of Dalmatia; in 1561 we find him as the confraternity's syndic, while from 1562 until 1564 he served as its president. During his Roman stay, in 1563, Rozanović was a member of the defense team in a legal case mounted against Beccadelli's Ragusan vicar Šimun Menčetić; in 1564, through Beccadelli he met Muzio Calini, archbishop of Zadar (Zara), then residing in Rome. Calini's letters to Beccadelli indicate that he considered the possibility of appointing Rozanović as his vicar in Zadar. However, Rozanović decided to return to Korčula, where in 1565 he became a canon of the Korčula cathedral chapter as well as the chapter's archdeacon. As archdeacon, he organized the defense when in 1571 the Ottomans attacked Korčula and the Venetian governer fled from the city. Because of the crucial role played in the battle by himself, by his father and by his brother Vice, Antun sought to obtain a reward from the Venetian authorities in the form of a simple ecclesiastical benefice, hoping that it would help his family recover from the damage the Turks caused to their land and property. Various surviving documents, most of them drafted by Antun, paint a detailed picture of the 1571 battle and its aftermath, providing a new context for the reading of his Latin work Korčula Defended from the Turks. In December of 1571 Rozanović traveled to Venice, where he hoped to receive a positive response to his family's supplication; from there he wrote to Beccadelli asking him to support his case in both Venice and Rome. In 1572 he is again found in the records of the University of Padua, where he attended the graduation ceremony of Bernardino Tespi from Udine; during the same period the records of the Korčula cathedral chapter regularly mention him as absent from the city and the diocese. A sixteenth-century manuscript connected to the convent of St. Prosdocimo in Padua, featuring a Latin poem Rozanović wrote about Blessed Eustochium, describes Rozanović as the spiritual father of the Benedictine nuns there in 1573. In 1574, as a mansionario in Padua, Rozanović resigned from the post of archdeacon in Korčula. He died in Padua in 1580.