1578

1578 (MDLXXVIII) was a common year starting on Wednesday in the Julian calendar.

 Events 
 January 31 – Battle of Gemblours – Spanish forces under Don John of Austria and Alexander Farnese defeat the Dutch. Don John begins to recover control of the French-speaking Southern Netherlands
 August 4 – Battle of Al Kasr al Kebir – The Moroccans defeat the Portuguese. King Sebastian I of Portugal is defeated and killed in North Africa, leaving his elderly uncle, Cardinal Henry, as his heir. This initiates a succession crisis in Portugal.
 October 1 – Alexander Farnese, Prince of Parma, succeeds Don John as Spanish Governor-General of the Netherlands.
 Martin Frobisher held the first celebration of Thanksgiving by Europeans in North American at Newfoundland by the Frobisher Expedition.
 Tibet – Sonam Gyrso receives from prince Atlan Khan the title of "Talaï" and becomes the third Dalai Lama.
 Battle of Wenden – The Russians are defeated by the Swedes, who proceed to take Polotsk.
 The Ottoman Empire conquers Abkhazia.
 Sixth and so far the last outbreak of the sweating sickness in England