The Hohenzollern family came originally from south-west Germany; their name derives from their 13th century castle of Zollern, near Stuttgart, Germany. Later, they became rulers of Nuremburg?. Nonetheless, the real importance of the Hohenzollerns began with their being granted the rank of Elector for the Holy Roman Empire in 1415. The first Hohenzollern Elector, Friedrich I of Brandenburg, obtained Brandenburg at about the same time; these lands would form the core of the family's power for the next five hundred years.
In chronological order, and grouped according to their most important title, the Hohenzollern rulers were:
Margraves of Brandenburg
Dukes of Prussia
Kings in Prussia
German Emperor
The Hohenzollern family continues to exist, and since Wilhelm's death the scions have been:
A cadet branch of the Hohenzollerns, the Hohenzollern-Sigmaringens, were also important landowners in pre-German Empire Germany, and later were the kings of Romania. They are also of note for being, in 1870, candidates for the throne of Spain. Wrangling between France and Prussia over this fact led to the [Franco-Prussian War]? and the founding of the German Empire.