The Holy Roman Empire (HRE; German: Heiliges Römisches Reich (HRR), Latin: Imperium Romanum Sacrum (IRS), Italian: Sacro Romano Impero (SRI)) was a realm (Reich) that existed from 962 to 1806 in Central Europe. It was ruled by the Holy Roman Emperor. Its character changed during the Middle Ages and the Early Modern period, when the power of the emperor gradually weakened in favour of the princes. In its last centuries, its character became quite close to a union of territories.