The House of Arenberg is an aristocratic lineage that is constituted by three successive families that took their name from Arenberg, a small territory of the Holy Roman Empire in the Eifel region. The inheritance of the House of Croÿ-Aarschot made the Arenbergs the wealthiest and most influential noble family of the Habsburg Netherlands. The family's Duchy of Arenberg was mediatized in 1810. As such, the Arenbergs belong to the small group of families that constitute the Hochadel.