Events January–March January 1 – The Greek Constitution of 1822 is adopted by the First National Assembly at Epidaurus. January 3 - The famous French explorer, Aimé Bonpland, is made prisoner in Paraguay accused of being a spy. January 7 – The first group of freed slaves from the United States arrive on the west coast of Africa, founding Monrovia on April 25. January 9 – The Portuguese prince Pedro I of Brazil decides to stay in Brazil against the orders of the Portuguese King João VI, beginning the Brazilian independence process. January 13 – The design of the modern-day flag of Greece is adopted by the First National Assembly at Epidaurus, for their naval flag. January 14 – Greek War of Independence: Acrocorinth is captured by Theodoros Kolokotronis and Demetrios Ypsilantis. February 6 – Chinese junk Tek Sing sinks in the South China Sea, with the loss of around 1,600 people on board. February 9 – The invading Haitian forces, led by Jean-Pierre Boyer, arrive in Santo Domingo, to overthrow the newly founded Dominican Republic. February 24 – The first Swaminarayan temple, Kalupur Swaminarayan Mandir at Ahmedabad in the British Raj, is inaugurated. March 19 – The Holy Alliance sends the Ottoman Empire a final ultimatum after Ottoman repression of Austrian subjects in Bucharest during the Wallachian uprising, otherwise facing war with Austria. March 19 – Boston, Massachusetts, becomes a city following a vote. March 31 – Greek War of Independence – Chios massacre: 20,000 Greeks on the island of Chios are slaughtered by Ottoman troops, and 23,000 exiled. April–June April 25 – The American Colonization Society lands at Cape Mesurado on the West African coast, after purchasing of coastline. The settlement will soon become Monrovia, as the nation of Liberia is established to fill the ACS mission of freeing black American slaves and sending them "back to Africa". April 30 – President of the Board of Control in the House of Commons, George Canning, moves to repeal a law that prohibited Roman Catholic peers from sitting or voting in the House of Lords; the motion passes, 235–223, on its second reading, but the House of Lords declines to pass it. May 16 - Nairs, the upper caste in British Raj, attack Sandar women for covering their upper body and breasts. May 24 – Battle of Pichincha: Simón Bolívar secures the independence of Quito. May 25 – Christos Palaskas