This expansion, as its name suggests, adds to the timeline of the original game that ended in 1789 to encompass the Napoleonic wars, up to 1820 along with new events and event chains, such as revolutions, changing the location of one's capital and the dismantling of the Holy Roman Empire.
Trade: One common player complaint about EU3 was the requirement to micro manage the sending of merchants to various Centers of Trade (CoT). Napoleon's Ambition allows the player to auto-send merchants to the CoT's of his/her choice, along with three levels of precedence deciding which CoT's to send to first. CoT's outside of a country's original area now start out as closed, so after discovering new trade centers in the east or the new world, one needs to use either diplomacy or war to gain access to the new markets. There is now also the possibility of opening new trade centers.
Colonization: The race for colonization was generally regarded as happening too early in the game, so the concept of Colonial Range has been introduced. It is based on one's level of naval technology, and prevents you from colonizing too far from an established city.
Interface: Several new ledger pages makes have been added to make it easier to choose where to build what and and to give easier access to information. The trade overlay map that previously only showed the coverage of the CoT's now also shows which goods are produced where, allowing for less random clicking when deciding on where to place manufactories.
Additional options have been added to customize gameplay. Players will now have options for "No Inflation", "Free Colonisation", "AI Aggressiveness", "Historical Monarchs", etc.