(pā'thrō tā'lyāth hērōn' dū'kā thā ōsū'nä) , 1579–1624, Spanish general and administrator. As viceroy of Sicily (1611–16) and of Naples (1616–20), he arrogated power to himself and fought the Ottomans and Barbary pirates. In 1617, suspecting Venetian anti-Spanish activities, he defeated a Venetian fleet in the Adriatic. In 1618 the Venetians accused him of plotting to overthrow the Venetian republic and Osuna was recalled (1620) to Spain and imprisoned (1621). Historians disagree on whether there was an actual conspiracy.