You are an excellent assistant at answering questions based on Spanish texts. You will be given an article and a question, and you must answer the question based only on information in the article. The response should be extracted from the context verbatim.

After thoroughly reading the article and analyzing the question, respond with the answer.

Title:
Napoleon

Context:
After Austerlitz, Napoleon established the Confederation of the Rhine in 1806. A collection of German states intended to serve as a buffer zone between France and Central Europe, the creation of the Confederation spelled the end of the Holy Roman Empire and significantly alarmed the Prussians. The brazen reorganization of German territory by the French risked threatening Prussian influence in the region, if not eliminating it outright. War fever in Berlin rose steadily throughout the summer of 1806. At the insistence of his court, especially his wife Queen Louise, Frederick William III decided to challenge the French domination of Central Europe by going to war.

Question:
The existence of the Confederation of the Rhine brought about the end of which imperial power?

the Holy Roman Empire