Until 1816 Waldeck was divided into nine Ämter (administrations): Arolsen, Eilhausen, Eisenberg, Landau, Lichtenfels, Rhoden, Waldeck, Wetterburg and Wildungen. In 1816 these were combined into five Oberämter: Rhoden and Eilhausen became Oberamt Diemel located in Rhoden, Arolsen, Wetterburg and Landau were combined into Oberamt Twiste located in Arolsen, Waldeck became part of Oberamt Werbe, located in Sachsenhausen, Wildungen became Oberamt Eder, situated in Alt-Wildungen. Lichtenfels (Sachsenhausen) remained independent until 1848 and then became part of Amt Eisenberg. 1849/50 the dukedom of Waldeck was divided into counties: Eder (seat in Wildungen), Eisenberg (seat in Korbach), Twiste (seat in Mengeringhausen, since 1857 in Arolsen). Oberämter Eder and Werbe as well as Freienhagen (formerly part of Twiste) became part of the county of Eder. Strothe and Meineringhausen became part of county Eisenberg. Oberämter Twiste and Diemel became part of Twiste, added was the county of Pyrmont.
In 1974 the Landkreis Waldeck was annexed to the county Frankenberg and became known as the Landkreis Waldeck-Frankenberg. The city of Züschen, for centuries belonging to Waldeck, became part of the city of Fritzlar in the county of Schwalm-Eder.
Source: Wikipedia http://de.wikipedia.org/wiki/Waldeck