The Berlin Decree was issued by Napoleon on November 21, 1806, following the French success against Prussia

Prussia

Prussia was a German kingdom and historic state originating out of the Duchy of Prussia and the Margraviate of Brandenburg. For centuries, the House of Hohenzollern ruled Prussia, successfully expanding its size by way of an unusually well-organized and effective army. Prussia shaped the history...

 at the Battle of Jena. The decree forbade the import of British

United Kingdom of Great Britain and Ireland

The United Kingdom of Great Britain and Ireland was the formal name of the United Kingdom during the period when what is now the Republic of Ireland formed a part of it....

 goods into European countries allied with or dependent upon France, and installed the Continental System

Continental System

The Continental System or Continental Blockade was the foreign policy of Napoleon I of France in his struggle against the United Kingdom of Great Britain and Ireland during the Napoleonic Wars. It was a large-scale embargo against British trade, which began on November 21, 1806...

 in Europe.
It eventually led to economic ruin for France, while little happened to the economy of Britain, which had control of the Atlantic Ocean trade. Other European nations removed themselves from the Continental System, which led in part to the downfall of Napoleon. The Milan decree

Milan Decree

The Milan Decree was issued on December 17, 1807 by Napoleon I of France to enforce the Berlin Decree of 1806 which had initiated the Continental System. This system was the basis for his plan to defeat the British by waging economic warfare...

for the same purposes was issued the next year.