United Duchies of Jülich-Cleves-Berg
The United Duchies of Jülich-Cleves-Berg was a combination of states of the Holy Roman Empire. The duchies of Jülich and Berg united in 1423. Nearly a century later, in 1521, these two duchies, along with the county of Ravensberg, fell extinct, with only the last duke's daughter Maria von Geldern left to inherit; under Salic law, women could only hold property through a husband or guardian, so the territories passed to her husband—and distant relative—John III, Duke of Cleves and Mark as a result of their strategic marriage in 1509. These united duchies controlled most of the present-day North Rhine-Westphalia that was not within the ecclesiastical territories of Electoral Cologne and Münster.