Matilda married Henry V, King of the Romans, at Mainz, becoming queen-designate of the Holy Roman Empire.
On 7 January 1110, at a grand ceremony in Mainz, the eight-year-old Matilda was formally betrothed and married to Henry V, King of the Romans, later Holy Roman Emperor. The marriage had been negotiated years earlier as part of an alliance between England and the Empire, and Matilda had already been sent to Germany around 1109/1110 to be raised at the imperial court in preparation for her role.
This union was a major diplomatic achievement for her father, Henry I of England, linking the Anglo-Norman realm with the most powerful secular ruler in Christendom. For young Matilda, it meant immersion in German language, customs, and politics from childhood, effectively transforming her into a continental royal figure rather than simply an English princess.
The marriage marked the beginning of Matilda's formal political education, as she would spend over a decade at the German court learning the mechanics of imperial governance, ceremony, and diplomacy — experience that would prove invaluable in her later struggle for the English throne. It also set a precedent of transnational queenship that distinguished her from most other royal women of her era, who typically remained within a single kingdom's court culture.