1055

Coin of Empress Theodora (980–1056)

1055 (MLV) was a common year starting on Sunday of the Julian calendar.

Events

January 11 – Emperor Constantine IX Monomachos dies after a 12½-year reign at Constantinople. He is succeeded by Theodora (a sister of the former Empress Zoë), who is proclaimed by the imperial guard (with strong opposition from the council) as empress of the Byzantine Empire.

King Ferdinand I of León ("the Great") begins his campaign against al-Andalus. He conquers Seia from the Christian allies of the Muslim taifas.<ref name=picard2000>Template:Cite book</ref> In a drive to consolidate his southern border in Portugal he re-populates the city of Zamora with some of his Cantabrian (montañeses) subjects.

October 24 – Ælfgar, Earl of Mercia, is outlawed by the witan ("meeting of wise men"). In revenge he builds a force and allies himself with the Welsh king Gruffydd ap Llywelyn. After defeating Ralph the Timid (a nephew of King Edward the Confessor), they attack Hereford and raid the church – taking everything of value, leaving the building on fire. The rebels also attack Leominster.
Edward the Confessor gives Tostig Godwinson (upon the death of Earl Siward) the important position as earl of Northumbria and the difficult mission of bringing the northern state under control.<ref>Template:Cite web</ref>

Winter – The Seljuk Turks led by Sultan Tughril capture Baghdad and enter the city in a Roman-styled triumph. Al-Malik al-Rahim, the last Buyid emir in Iraq, is taken prisoner.

Construction on the Liaodi Pagoda in Hebei is completed (the tallest pagoda in Chinese history, standing at a height of 84 m (275 ft) tall).

King Andrew I of Hungary ("the Catholic") establishes the Benedictine Tihany Abbey. Its foundation charter is the earliest written record extant in the Hungarian language.
April 13 – Pope Victor II succeeds Leo IX as the 153rd pope of the Catholic Church in Rome (until 1057).