- Spain, fearing another revolt by Carlist supporters, as well as having a more general lack of money from the previous revolt, decide to take President Polk of the United States up on his offer of purchasing their main colony in the Caribbean, Cuba, for $100 million - This did not include the island Puerto Rico.
- With tensions reaching a fever-pitch between the 'Free' States and the 'Slave' States the electorally dominant northern states elect a reactionary, anti-slavery President into the White House - Charles Sumner.
- Days after Britain declares war on the Union, the French follows suit.
- In the late months of 1861 President Sumner is killed by a pro-Confederate assassin. His Vice President - William Seward, an ardent Unionist and American expansionist - took over as President.
- The Spanish Empire is offered the Dominican Republic by its President, as the nation was in economic turmoil. Isabella accepts, and so the Dominican Republic is re-annexed into the Spanish Empire as Saint Domingo, it rapidly comes to dominate Spain's Empire in the Caribbean.
- After the Dominican Civil War, the Spanish annex Haiti into the Spanish Empire as a protectorate, attached to Saint Domingo.
- The 1864 United States Presidential Election sees the 'Peace Democrat' candidate - Clement Vallandigham - win by a landslide.
- The American Civil War finally draws to a close in the early months of the year. The Americans were forced by the Anglo-French-Confederate Alliance to sign the Treaty of Washington, in which the Confederacy was recognised as independent. The USA also had to pay war indemnities to the three nations - $900 million to Britain, $400 million to France and the highest amount of $2 billion went to the Confederate States.
- In Mexico Napoleon III had used the American Civil War as an excuse to pump more French troops into what he planned would eventually become a part of the French Empire, by the end of the American Civil War there were around 100,000 French troops in Mexico and the Mexican Civil War kicked off the year after the US Civil War ended.
- In the Nine Weeks War the Prusso-Italian Alliance occupied Vienna and the Austrian Empire was forced to sign the humiliating Peace of Vienna, in which it ceded Venetia and Dalmatia to the Italians, and also had to cede the areas of northern Bohemia which were populated by Germans to Prussia, as well as Austrian Silesia.
- In the Peace of Vienna Prussia also annexed numerous German states, the most important of which was Saxony which was immediately made a Prussian province that was expanded into northern Bohemia. In the Kingdom of Hanover the Hanoverian's were allowed to stay on as the rulers, however George V refused to sign the Peace of Vienna and so willingly abdicated in favour of his son, who then became King Ernest Augustus II and went on to sign the peace treaty.
- In October the Luxembourg Crisis had begun, in which Otto von Bismark, Chancellor of Prussia, refused to allow Napoleon III of France to purchase the Grand Duchy of Luxembourg from King William III of the Netherlands, despite having told Napoleon that he would allow it.
- The Luxembourg Crisis rumbled on into November when a new crisis had sprung up in which Garibaldi, an Italian nationalist, had attacked Rome with a band of Italian volunteers who were secretly funded and armed by the Italian King, Victor Emmanuel II. Garibaldi, in a rapid campaign, had managed to defeat the Franco-Papal forces and had taken the whole of Rome. By the time Garibaldi had reached the Vatican, though, the Pope had managed to escape, being taken on British vessels destined for Malta.
- Despite international attempts to settle the individual crises in each nation, both Italy and Prussia supported each other in their endeavours. Napoleon took this as a personal affront and, thus, the Franco-Prussian War began which would see Napoleon III's France against Bismark's Prussia and Victor Emmanuel II's Italy (in Italy the war was called the 'Fourth Italian War of Independence').