The House of Cantacuzino is a Romanian aristocratic family of Greek origin. The family gave a number of princes to Wallachia and Moldavia, and it claimed descent from a branch of the Byzantine Kantakouzenos family, specifically from Byzantine Emperor John VI Kantakouzenos. After the Russo-Ottoman War of 1710–11, a lateral branch of the family settled in Russia, receiving the princely status. In 1944, Prince Ștefan Cantacuzino settled in Sweden, where his descendants form part of the unintroduced nobility of that country.

The boyars of Moldavia and Wallachia were the nobility of the Danubian Principalities of Moldavia and Wallachia. The title was either inherited or granted by the Hospodar, often together with an administrative function. The boyars held much of the political power in the principalities and, until the Phanariote era, they elected the Hospodar.