Originally, Britain was the only country that successfully evaded Napoleon's grasp. To push Britain into yielding, Napoleon initiated an economic embargo on Britain, cutting off trade. The Iberian Peninsula War is the event where Spanish and Portuguese forces fought off France. The long-standing Peninsular war interested the British forces that later on led them to join-in. At this time, Russia was adamant to suffer due to the economic embargo on Britain. The effect on Russia was costly. Russia then started to disobey France that led to the massive invasion. This invasion of Russia led to the beginning of the downfall of Napoleon. When France was unsuccessful in conquering Russia; Austria, Prussia and Sweden (originally coerced into teaming up with France) was encouraged by this defeat. They joined forces with Britain to fight off France in what we know as the Battle of Leipzig. Thus these two events were important milestones in Napoelon's defeat.