Schwarzburg-Sondershausen was a small principality in Germany, in the present day state of Thuringia, with its capital at Sondershausen.

Christian William I of Schwarzburg was Count and later Prince of Schwarzburg-Sondershausen, Count of Hohenstein, Lord of Sondershausen, Arnstadt and Leutenberg. From 1681, he also carried the title of Count in Ebeleben, and from 1716 Count in Arnstadt.