Oriental Crisis (1838 or later, Common) Egypt begins the game as an Ottoman vassal. Sometime within the first ten years of the game it will rebel, and the Ottomans will likely be engulfed in a war to reclaim the Levant. Egypt is a strong opponent, and suddenly European powers will be put on the spot to either support the crumbling Ottomans or intervene on Egypt's behalf despite the objections of the Ottomans and their supporters.
Irish Famine (1840's, Always) The Irish Potato Famine will begin in the early part of the Liberal Revolution, kicking off a series of events which will plague the United Kingdom for the rest of the game as the Irish fight for fair treatment and then independence.
French Revolution (1845-1850, Sometimes) As the Liberal Revolutions spread through Europe, Napoleon III will rise up and overthrow the French monarchy should militancy there become too high. This starts a series of events as Napoleon then installs a monarchy during the first election and then he himself is possibly overthrown in the years to come.
The Schleswig-Holstein Question (1848, Common) Schleswig and Holstein are united into a single country under the vassalage of Denmark, which will try to annex them at the height of the Liberal Revolution. This will cause Holstein to rebel, and very likely bring in Prussia and even Austria to its defense. Freedom for Schleswig-Holstein, however, will lead to immediate conflict between Prussia and Austria as they attempt to answer the problem of who should have influence there.
American Civil War (1854 or later, Almost Always) The United States of America starts the game as the only Democratic Great Power, but also as one in which slavery is still legal. As America becomes more conscious of the Slavery Debate, Confederate cores will begin to spread across the South, and will eventually culminate in the Confederate States of America declaring independance from the US. Either way, the Slavery Debate will be settled one way or another, whether the CSA is able to maintain independance or is reannexed by the USA. (FOR APD ONLY)
Crimean War (1850's or later, Sometimes) Once the Ottoman Empire falls out of great power status and France researches State & Government, France will attempt to claim influence over the Holy Land if the Ottomans own it. This will prompt a reaction from Russia as it steps in to defend eastern Christians, and a war which will eventually lead to The Treaty of Paris-- either in Russia's favor if they win, or marking the first major Russian setback in the Balkans if they lose.
The Taiping Rebellion (1850's, Common) As Hong Xiuquan and his Christian followers spread their influence within the Qing Empire, rebellion threatens... eventually breaking out into all-out war as the Heavenly Kingdom secedes and starts a civil war to take over all of China. Regardless of the outcome, this will herald the end of Manchu dominance within China forever.
Meiji Restoration(1850's-1860's, Common) Japan is split into feudal states, ruled over by the Shogun-- but the fracture between the Shogun and the tozama daimyo turns into a war when Meiji becomes the new Emperor. Thus begins the Boshin War, putting Japan onto the road of modernization. (FOR APD ONLY)
Alternate American Civil War (1865 or later, Rare) If the United States is able to avoid having the CSA declare independance by appeasing southern slavers, northern abolitionists will become discontent in the Slavery Debate. Eventually, the Free States of America will seceed from the United States in an attempt to end slavery in the north. (FOR APD ONLY)
Congress of Berlin: (1860's - 1870's, Common) Should the Ottoman Empire fall below great power status and do poorly enough, the Congress of Berlin event chain will begin, resulting in Russia and the other great powers of Europe meeting to decide how the Balkans should be divided for the good of all Europe-- is it important that the Ottomans be kept strong, to check Russian power, or is it more important that Russia be appeased and stability in the region take priority?
Disunited States: (Anytime after the Civil War, Rare) If the USA falls to tyranny, the Sons of Liberty will rise once again and start a chain of events that can lead to the breakup of the nation. Individual American states can secede and possibly re-unite the CSA or the northern Free States of America, engaging the old USA in a second civil war for control over America's destiny.
Warlord Era: (1900's or later, Common) As the Chinese develop more military techs, eventually they will get the "New Army" event which relegates power to regional generals... this spreads cores for the warlord cliques throughout China, leading to their eventual separaton from China if the country either does very poorly or reforms too quickly. The cliques will then battle each other in a civil war to reunite the country as either Nationalist China, Beiyang China or even Communist China.
First Opium War (1836-1840's, Common): the Canton Incident will trigger a demand for British extraterritoriality in the Qing Empire, which they are likely to refuse... causing a war to take Hong Kong (and the first of the Unequal Treaty decisions for the Qing Empire).
Peru-Bolivian Confederation (1836, Always): At the game start, Peru, South Peru and Bolivia have just made a confederation into a single country-- strongly objected to by Chile and Argentina, who will swoop in to take back their cores. This results in Peru stabbing the Confederation in the back, and making things very difficult-- if not impossible-- for the Confederation to survive. If, however, the PBC survives intact until 1840, it can trigger the Treaty of La Paz decision, which will grant the PBC cores on all of Peru. If the PBC survives several more decades, it can later take a decision that will annex both Perus to the PBC permanently.
United States of Central America (1836, Always): At the beginning of the game the USCA is facing large amounts of dissent to the Federal government by the residents of the various central American provinces. El Salvador, Nicaragua, Honduras, and Costa Rica will individually attempt to declare independace. If the Federal forces cannot restore order, the USCA will collapse and Guatemala will have to accept the central american union is over. Similarly to Yugoslavia, Romania, and the United Baltic Provinces, a great power may reunify the USCA as a vassal ally.
Mexican Rebellion (1836, Always): Mexico begins the game in PDM as a dictatorship under Antonio López de Santa Anna, struggling not only with the secession of Texas but also rebellions in other parts of the nation. If Texas succeeeds, things get worse as other states attempt to secede, namely the Yucatan and Rio Grande republics. The loss of territory will in turn trigger further instability and rebellions across Mexico.
The Treaty of Guadelupe Hidalgo (1840's to 1850's, Sometimes): Should the USA get Mexico in its sphere, it will demand all of its cores in the southwest... a demand which will very likely start a war to settle the matter once and for all. Either way, should the Americans occupy their states, they will be able to sign a treaty with Mexico that forces the land to be turned over in its entirety.
The Great Game (1840's and after, Always): As United Kingdom secures its hold over India, the Russian Empire begins to look southward into Central Asia for room to expand their own colonies. Fearing Russian influence spreading into the British realm, the United Kingdom moves north to oppose them. Thus the scramble to dominate Central Asia begins between Britain and Russia.
The Oregon Treaty (1845-1850, Common): Once all of the Oregon Country is settled by the British and the Americans, an American election will start a chain of events as politicians claim the right to expand north to the 54th parallel. This can result in the historical devision of Oregon between the two at the 49th parrallel, or can lead to outright war as treaty talks break down.
Hungarian War for Independence (1847-1850, Common) At the height of the Springtime of Nations, the Hungarians will declare their independence from Austria, likely leading to a war as the Austrians move in to stop them and the Russians possibly intervene on Austria's behalf.
The Argentine Constitution (1850's, Common): If Argentina is still a dictatorship after 1850, and has a lot of liberals or a large amount of militancy, Entre Rios will secede-- though not without first seeking allies among neighbors such as Brazil. Should Entre Rios not be conquered in the ensuing war, it will rejoin Argentina and turn the country into a democracy with a new constitution.
Sepoy Rebellion (1857, Always): The Sepoy Rebellion represents the first major uprising in British India, and the point in which rebels in the sub-continent will band together into a single group.
Stirrings of Indian Nationalism (after 1870, Always): Once any nation in India researches Revolution & Counterrevolution, the first ideas of India as a single state-- and thusly the first formation of Indian pan-nationalist rebels-- will occur. Rebellions will become a problem in both British India as well as British vassals in the region.
The Danubian Federation (after 1870, Rare): Should Austria-Hungary be in a position to propose the Danubian Federation, it can initiate talks with the various ethnic minorities in its empire; in an attempt to duplicate the Hungarian compromise on a larger scale. If it succeeds, the result will be a vast multi-cultural empire the likes of which Europe has never seen.
The Boer War (1870's, Common): Starting with a British objection to Boer treatment of uitlanders, this can lead to both Transvaal and Oranje declaring war on the British. If they occupy all of South Africa, they will automatically annex it and unite into a Boer-led South African nation.
Scramble for Africa (1880's, Always): As Africa becomes open for settlement, the nations of Europe will meet to agree on the "proper" way to proceed with colonialization... suddenly making the establishment of African protectorates very cheap and starting the race for all colonial nations to take over the entire continent.
The Arab Revolt: (1900's, Common) Both Mashriqi and Bedouin countries that are under the control of another civilized nation will begin revolting anytime after 1900 when Revolution & Counterrevolution is researched.
Brazilian Irredentism: Brazil begins the game at war with the breakaway republic Rio Grande do Sul, which is almost always swiftly destroyed. Afterwards, if Brazil becomes a great power, it can take a decision that grants it cores on all of Uruguay. If Brazil wins and annexes Uruguay, it can then take a decision that grants it cores on some Argentinian provinces in the north.
Force Satellite Release: If a great power gets another nation's vassal into their sphere of influence, and militancy in that country gets high enough, it can enact the "We Shall Be Free" decision. This offers their sphere owner a choice: either promote a coup to free the vassal, risking influence there and relations with their overlord, or allow the opportunity to pass and lose influence for certain.
Great Wars: Incorporating the Great Wars mini-mod, this ups the ante in the later portion of the game. Once Mass Politics has been researched, great powers that go to war will suddenly call in their allies on a regular basis... and seek out new allies from among their enemy's enemies even as the war is underway. This can quickly lead to some very large wars, and when a nation loses the war it may be dismantled-- resulting in a large loss of territory and colonial holdings to all the nations it was at war with.
Infamy Wars: Players who disregard the 25 Infamy limit will now find themselves having a much harder time in PDM. Taking infamy too high will result in a nation becoming an International Pariah, leading the other great powers of the world to band together in a great war to stop you-- even if the Great Wars system has not yet been activated.
World Fairs: The World Fair events have been revamped. Now they start every decade after 1850, as the great powers compete to be the new World Fair venue and then attending countries compete for the chance to earn prestige.