Events in Poland
February 21 - The Central Economic Society for the Grand Duchy of Poznań was established.
February 27 - patriotic demonstration in Warsaw bloodily suppressed by the Russian army; 5 fallen.
March 2 - in Powązki there was a demonstration funeral of five killed by the tsarist army on February 27.
April 7 - Russian officer Jan Peucker committed suicide, not wanting to shoot the participants of the patriotic march in Warsaw.
April 8 - the Russian army opened fire on the defenseless people gathered in the castle square in Warsaw; 100 killed and hundreds injured.
June 18 - Tsar Alexander II Romanov issued a decree establishing the Council of State and provincial and district self-government in the Congress Kingdom.
October 14 - Russian governor Count. Karol Lambert introduced martial law on the territory of the Kingdom of Poland.
October 15 - in Warsaw, the Russian army crashed a patriotic demonstration on the anniversary of the death of Tadeusz Kościuszko.
October 24 - the Toruń - Bydgoszcz railway line was opened.
November 4 - the Vienna - Lviv railway line was opened.
December 1 - a 45.3 km long, 2-track railway line from Łowicz to Kutno was launched
January 2 - the Prussian king Frederick William IV died; his younger brother, William I, ascended the throne.
Mississippi left the Union as the second southern state.
the Star of the West steamboat, which attempted to deliver supplies to Major Robert Anderson's garrison at Fort Sumter, was fired upon by Confederate batteries and forced to retreat; these shots turned out to be the first in the Civil War.
January 19 - Georgia left the EU.
January 11 - Alabama left the EU.
January 26 - Louisiana left the EU.
January 29 - Kansas admits to the EU as the 34th state.
February 4 - A group of the US southern states seceded and formed a new state, the Confederate States of America.
February 9 - The newly formed Confederate States of America elected Jefferson Davis as their president.
February 18 - Victor Emmanuel II became the first king of a united Italy.
February 26 - Austrian Emperor Franz Joseph I issued the February Patent.
March 2 - Dakota Territory and Nevada Territory created.
March 3 - (February 19, old style) Alexander II issued a manifesto announcing the abolition of serfdom and the enfranchisement of peasants in the Russian Empire.
Abraham Lincoln, the 16th president of the United States of America, was sworn in.
German astronomer Ernst Tempel discovered the asteroid (64) Angelina.
March 8 - Astronomer Ernst Tempel discovered the asteroid (65) Cybele.
March 14 - Jacob van Zuylen van Nijevelt becomes Prime Minister of the Netherlands.
March 16 - The Confederate States Marine Corps was created.
March 17 - the all-Italian parliament in Turin proclaimed the establishment of the Kingdom of Italy (Victor Emmanuel II became the king).
March 20 - over 5,000 People died in the Argentinian city of Mendoza, devastated by the earthquake.
March 23 - Camillo Cavour became the first prime minister of a united Italy.
March 29 - Austrian Silesia regained its autonomy with its attributes in the form of the Silesian National Seym and the national government in Opava.
April 2 - Napoleon Bonaparte's body was moved from one of the chapels to the sarcophagus under the dome of the Church of the Invalids in Paris, where they rest to this day.
April 6 - The Sultanate of Zanzibar was established.
April 8 - the Bulgarian Catholic Church was established.
April 10 - Massachusetts Institute of Technology was established in Cambridge near Boston.
April 11 - The premiere of the opera The Statue of Ernest Reyer took place in Paris.
April 12 - the shelling of Fort Sumter by the troops of the Confederation of the South initiated the Civil War of 1861–1865.
April 14 - American Civil War: Confederate Army Victory in Battle