Complex sentence: 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 that was the basis for his plan to defeat the British by waging economic warfare.
Split into simpler sentences: 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.