Died in 1578

Jan 5 Giulio Clovio an illuminator, miniaturist, and painter born in the Kingdom of Croatia, who was mostly active in Renaissance Italy. He is considered the greatest illuminator of the Italian High Renaissance, and arguably the last very notable artist in the long tradition of the illuminated manuscript, before some modern revivals
Feb 12 Catherine of Austria Queen of Portugal Queen of Portugal as wife of King John III, and regent during the minority of her grandson, King Sebastian, from 1557 until 1562.
Mar 3 Sebastiano Venier Doge of Venice from 11 June 1577 to 3 March 1578.
Mar 7 Margaret Douglas the daughter of Archibald Douglas, 6th Earl of Angus, and Margaret Tudor, Queen Dowager of Scotland. In her youth she was high in the favour of her uncle, King Henry VIII, but twice incurred the King's anger, first for her unauthorised engagement to Lord Thomas Howard, who died in the Tower of London in 1537 because of his misalliance with her, and again in 1540 for an affair with Thomas Howard's nephew Sir Charles Howard, the brother of Queen consort Catherine Howard. On 6 July 1544, she married Matthew Stuart, 4th Earl of Lennox, one of Scotland's leading noblemen. Her son Henry Stuart, Lord Darnley, married Mary, Queen of Scots and was the father of James VI of Scotland
Mar 7 Gilles de Gouberville a French diarist. His journals were translated into English by Katharine Fedden
Mar 8 Elisabeth of Brandenburg-Küstrin a princess of Brandenburg-Küstrin and margravine of Brandenburg-Ansbach and Brandenburg-Kulmbach by marriage.
Mar 17 Cornelis Cort a Dutch engraver and draughtsman. He spent the last 12 years of his life in Italy, where he was known as Cornelio Fiammingo
Mar 29 Arthur Champernowne an English politician, high sheriff and soldier who lived at Dartington Hall in Devon, England.
Mar 29 Louis I Cardinal of Guise the fourth son of Claude, Duke of Guise and Antoinette de Bourbon, and the younger brother of Charles of Guise, Cardinal of Lorraine, and Mary of Guise, queen consort of King James V of Scotland. He was the nephew of Cardinal Jean de Lorraine. He is sometimes known as the cardinal de Guise
Apr 11 Joanna of Austria Grand Duchess of Tuscany born an Archduchess of Austria as the youngest daughter of Ferdinand I, Holy Roman Emperor, and Anna of Bohemia and Hungary. By marriage, she was the Grand Princess of Tuscany and later the Grand Duchess of Tuscany. One of her daughters was Marie de Medici, second wife of King Henry IV of France
Apr 14 James Hepburn 4th Earl of Bothwell hereditary Lord High Admiral of Scotland. He is best known for his association with and subsequent marriage to Mary, Queen of Scots, as her third husband
Apr 19 Uesugi Kenshin a daimyo who ruled Echigo province in the Sengoku period of Japan.
Apr 20 Lady Mary Grey the youngest daughter of Henry Grey, 1st Duke of Suffolk, and Frances Brandon, and through her mother had a claim to the crown.
Aug 4 Abu Marwan Abd al-Malik I Saadi the Saadi Sultan of Morocco from 1576 until his death right after the Battle of Ksar El Kebir against Portugal in 1578.
Aug 4 Abu Abdallah Mohammed II Saadi the oldest son of Abdallah al-Ghalib and became the sultan of Morocco after his father's death.
Aug 4 Sebastian of Portugal King of Portugal and the Algarves from 11 June 1557 to 4 August 1578 and the penultimate Portuguese monarch of the House of Aviz.
Aug 4 Thomas Stukley an English mercenary who fought in France, Ireland, and at the Battle of Lepanto and was killed at the Battle of Alcazar. It was alleged that he was an illegitimate son of King Henry VIII. He was a Roman Catholic recusant and a rebel against the Protestant Queen Elizabeth I
Aug 11 Pedro Nunes a Portuguese mathematician, cosmographer, and professor, from a New Christian family. Nunes, considered to be one of the greatest mathematicians of his time, is best known for his contributions in the technical field of navigation, which was crucial to the Portuguese period of discoveries. He was the first to propose the idea of a loxodrome and was also the inventor of several measuring devices, including the nonius , named after his Latin surname
Sep 22 Archduke Wenceslaus of Austria a German prince and member of the House of Habsburg and since 1577 Grand Prior of the Order of Malta in Castile.
Oct 1 John of Austria