The history of Luxembourg is considered to begin in 963, when count Siegfried acquired a rocky promontory and its Roman-era fortifications known as ''Lucilinburhuc'', "little castle", and the surrounding area from the Imperial Abbey of St. Maximin in nearby Trier. Siegfried's descendants increased their territory through marriage, war and vassal relations. At the end of the 13th century, the counts of Luxembourg reigned over a considerable territory. In 1308, Count of Luxembourg Henry VII became King of the Germans and later Holy Roman Emperor. The House of Luxembourg produced four emperors during the High Middle Ages. In 1354, Charles IV elevated the county to the Duchy of Luxembourg. The duchy eventually became part of the Burgundian Circle and then one of the Seventeen Provinces of the Habsburg Netherlands.