1153

By place

Byzantine Empire

• Spring - Andronikos Komnenos, son of Isaac Komnenos, is imprisoned in the imperial palace for conspiring against his uncle, Emperor Manuel I at Constantinople.

  Levant

• August 19 - Siege of Ascalon: King Baldwin III of Jerusalem captures Ascalon, the last Fatimid fortress in Palestine. The citizens are allowed to leave in peace and return back to Egypt.
• Raynald of Châtillon, a French nobleman, marries Constance of Antioch and becomes Prince of Antioch.

  England

• Spring - The 19-year-old Henry of Anjou lands with a Norman fleet on the south coast of England. He defeats King Stephen with a small army at Malmesbury. Henry travels north through the Midlands, while a temporary truce is accepted. Robert de Beaumont, 2nd Earl of Leicester, announces his support for the cause. Hoping to dethrone Stephen and replace him with Matilda.
• May 24 – King David I dies after a 29-year reign at Carlisle Castle. He is succeeded by his grandson, the 12-year-old Malcolm IV. Malcolm is the eldest son of Henry, 3rd Earl of Huntingdon, who is crowned as ruler of Scotland at Scone Priory on May 27. Because of his young age, Donnchad becomes Malcolm's regent and royal adviser.
• August - Stephen assemble troops to renew the siege of Wallingford Castle in a final attempt to take the stronghold. Henry of Anjou marches south to relieve the siege, arriving with a small army of mercenaries. He places Stephen's besieging troops under siege themselves. Stephen agrees to make a truce and accepts Henry as heir to the English throne.
• November 6 - The Treaty of Wallingford: Henry of Anjou and Stephen ratifies the terms of a permanent peace under the direction of Archbishop Theobald of Bec. Ending the civil war – between England and Normandy after 18-years. The treaty grants the throne to Stephen for the duration of his life, but makes Henry the heir apparent.

  Europe

• Confronted with important financial difficulty due to the expenses of the Spanish crusade, the Republic of Genoa has to sell a third of the city of Tortosa to Ramon Berenguer IV, count of Barcelona.

  Asia

• February 10 - Taira no Tadamori dies after a career in which he has used his military and diplomatic skills to subdue the pirates menacing commerce in the Seto Inland Sea. He expands trade with China and becomes the first samurai to serve Emperor Konoe as personal bodyguard. He is succeeded by his son Taira no Kiyomori, who assumes control of the Taira Clan. He establishes the first samurai-dominated government in Japan.

  Africa

• King Roger II sends a Sicilian expedition under Admiral Philip of Mahdia to conquer Ifriqiya. With the support of Muslim troops, the Siculo-Normans suppress a rebellion on Djerba and invade the Kerkennah Islands.

  By topic

Demography

• Estimation: Constantinople, capital of the Byzantine Empire, becomes the largest city of the world, taking the lead from Merv in the Seljuk Empire.

  Religion

• July 8 - Pope Eugene III dies after a 8-year pontificate at Tivoli. He is succeeded by Anastasius IV as the 168th pope of the Catholic Church.
• Dhovemi, ruler of the Maldives, converts to Islam and adopts the Muslim title of Sultan Muhammad ibn Abdullah.