1558

January–March

• January 7 - French troops, led by Francis, Duke of Guise, take Calais, the last continental possession of the Kingdom of England, in the Siege of Calais.
• January 22 - The Livonian War begins.
• February 2 - The University of Jena is founded in Thuringia, Germany.
• February 4 - Takeda Shingen becomes the shugo of Shinano Province after his successful military campaign there.
• February 5 - Arauco War: Pedro de Avendaño, with sixty men, captures Caupolicán, who is leading their first revolt against the Spanish Empire, encamped with a small band of followers.
• March 8 - The city of Pori is founded by Duke John on the shores of the Gulf of Bothnia.

April–June

• April 17 - The siege of Thionville in the Duchy of Luxembourg, is started by the French Army, led by Francis, Duke of Guise.
• April 24 - Mary, Queen of Scots, marries Francis, Dauphin of France, at Notre Dame de Paris.
• May 3 - The Imperial Diet of the Holy Roman Empire gives recognition to Ferdinand as Holy Roman Emperor, two months after his proclamation on March 14 as the successor to his brother Charles V.
• June 13 - An armada of ships from the Ottoman Empire, dispatched by Sultan Suleyman the Magnificent at the request of King Henry II of France, sails into the Bay of Naples at Italy and attacks the city of Sorrento.
• June 23 - France is successful in the siege of Thionville in the Duchy of Luxembourg and recovers the fortress from the Spanish Empire after an operation that began on April 17 and lasted more than two months.

July–September

• July 9 - The Ottoman Empire, with 15,000 troops and 150 warships, besieges the Spanish garrison at Ciutadella de Menorca at Spain's Balearic Islands. When the town falls on July 17, the 3,099 surviving inhabitants are sold into slavery.
• July 13 - Battle of Gravelines: Near the border between the Kingdom of France and the Spanish Netherlands, Spanish forces led by Lamoral, Count of Egmont, and assisted by the English Navy, inflict a major defeat on the French forces of Marshal Paul de Thermes.
• July 18 - The city of Tartu, capital of the Bishopric of Dorpat surrenders to Russia.
• August 22 - In Spain, Bartolomé Carranza, the Catholic Archdiocese of Toledo|Roman Catholic Archbishop of Toledo], is arrested at Torrelaguna on orders of the Grand Inquisitor, Fernando de Valdés y Salas. Carranza is brought a prisoner to Valladolid to face accusations of heresy. He remains in prison for eight years before being transferred to Rome for the Pope to hear his appeal.

October–December

• October 17 - Postal history of Poland: King Sigismund II Augustus appoints an Italian merchant living in Kraków to organise a consolidated postal service in Poland, the origin of Poczta Polska.
• November 6 - On her deathbed, Queen Mary of England designates her half-sister, Elizabeth, as her successor. Both Mary and Elizabeth are daughters of the late King Henry VIII.
• November 15 - The five Canterbury Martyrs, three men and two women, are burned at the stake, becoming the last of 312 Protestants put to death for heresy during the reign of England's last Roman Catholic ruler, Queen Mary. Queen Mary dies two days later, bringing an end to her campaign. During the final year of Mary's reign, 49 Protestants are burned at the stake and three others die in prison while awaiting execution.
• November 17 - Queen Mary, a devout Roman Catholic dies of uterine cancer at the age of 42, and is succeeded by her younger half-sister Elizabeth, an adherent to the Protestant Church of England, beginning the Elizabethan era in British history.
• December 5 - Less than three weeks of becoming Queen of England, Elizabeth summons the members of the English Parliament with orders to assemble at Westminster on January 23. Under Elizabeth's agenda, the Parliament is charged with restoring the laws passed at the beginning of the English Reformation, and repealing the reforms made during the reign of Queen Mary.

Unknown

• John Knox's attack on female rulers, The First Blast of the Trumpet Against the Monstruous Regiment of Women, is published anonymously from Geneva.
• English explorer Anthony Jenkinson travels from Moscow to Astrakhan and Bukhara. He is the first Englishman to note that the Amu Darya changed course, to start flowing into the Aral Sea.
• Queen Elizabeth I of England grants rest and refreshment to pilgrims and travellers who pass by the Holy Well Spring at Malvern in England.

Ongoing

• 1557 influenza pandemic.