German invasion of Hungary (1063)

Background

After fifteen years in exile, Andrew I took the Hungarian throne in 1046 during a pagan revolt, defeating Peter Orseolo, a vassal of King Henry III of Germany. Andrew broke with his pagan supporters, restored Christianity, and outlawed pagan rites. In 1048 he recalled his younger brother Béla from exile, granting him one-third of the kingdom with the title of duke. The brothers cooperated closely, repelling Holy Roman Empire raids in the early 1050s.

Andrew's son Solomon was born in 1053. Their relationship deteriorated after Andrew had Solomon crowned king in 1057 or 1058, a condition of peace negotiations with the Empire, which required Solomon's succession rights to be declared before his marriage to Judith, sister of the minor Henry IV. According to the Annales Altahenses, Béla and his eldest son Géza were absent from the September 1058 meeting where Judith was betrothed to Solomon. Andrew then sought to secure the throne for his son.

The Illuminated Chronicle recounts that Andrew invited Béla to his manor in Várkony, offering him a choice between a crown and a sword, symbols of royal and ducal power, but had ordered Béla's murder if he chose the crown. Informed of the plan, Béla chose the sword. Some historians argue this story originated in the 12th century as retrospective justification for Béla's usurpation. Béla fled to Poland, returned with Polish reinforcements under Duke Boleslaus the Bold, and defeated Andrew in a civil war; Andrew was mortally wounded in battle in autumn 1060.

Béla was crowned king on 6 December 1060, while Solomon and his mother fled to the Holy Roman Empire, settling at Melk. In early 1061, Anastasia traveled to Regensburg to seek German help to restore Solomon.

The invasion

The imperial army invaded Hungary in late August 1063. German troops under Otto of Nordheim, Duke of Bavaria, crossed the border after 20 August 1063; Henry IV, who participated personally, issued a charter in Erlangen on that day. The army likely entered Hungary in early September 1063. Historian Ágoston Ignácz suggested the force set out from Melk, where Solomon's mother Anastasia was in exile, following the Danube toward Hungary.

The Hungarian western defense line, the gyepű, was easily crossed with help from Solomon's partisans, according to the Annales Altahenses. The castle of Moson was besieged and captured by the vanguard and main army. Hearing of the invasion, Béla I planned to abdicate in favor of his nephew if his former ducatus were restored, but he was seriously injured when his throne broke beneath him at Dömös. The dying king was taken to the western border and died at the creek Kőris near the river Rabnitz at Dévény Castle on 11 September 1063.

Historian Péter Báling viewed the death narration as topos and allegory, comparing it to Bishop Bruno of Würzburg, expressing that Béla had no legitimate claim. It is conceivable Béla died fighting the Germans. Historian Dániel Bagi argued the accidental death story alludes to the illegitimacy of his rule.

Aftermath

After the German withdrawal, Solomon's three cousins, Géza and his brothers, returned with Polish reinforcements. Solomon took refuge in Moson fortress.

Hungarian prelates led by Archbishop Desiderius mediated to avoid civil war. On 20 January 1064, an agreement was signed in Győr: Géza and his brothers acknowledged Solomon as lawful king, and Solomon granted them their father's former ducatus. They cooperated from 1064 to 1071, but relations remained tense and distrustful, leading to further war.