Queen of Italy (regina Italiae in Latin and regina d'Italia in Italian) is a title adopted by many spouses of the rulers of the Italian peninsula after the fall of the Roman Empire. The details of where and how the ruling kings ruled are in the article about them. The elective dignity of Roman Emperor was restricted to males only; therefore, there was never an Italian Queen regnant, though women such as Adelaide of Italy and Theophanu and Maria Theresa of Austria, who controlled the power of ruling, ruled as de facto Queens Regnant.
After 887, Italy fell into instability, with many rulers claiming the Kingship simultaneously:
In 951 Otto I of Germany invaded Italy and was crowned "King of the Lombards". In 952, Berengar and Adalbert became vassals, but remained Kings until being deposed by Otto.
After the brief interruption by Arduin of Ivrea and after the restoration of the Holy Roman Emperor as the sole holder of the title King of Italy, the title became one of the many appanages of the Holy Roman Empress.