Example image of eyePlorer eyePlorer map for '1811': Common year starting on Sunday Common year starting on Tuesday Gregorian calendar Julian calendar Roman numerals Charles Deslondes January 3 January 22 Juan Bautista de las Casas San Antonio Texas British Regency February 5 George III of the United Kingdom George IV of the United Kingdom Prince regent Egypt Mamluk March 1 Muhammad Ali of Egypt Muhammad Ali's seizure of power Battle of Lissa (1811) March 13 Commissioners' Plan of 1811 March 22 Great Comet of 1811 Honoré Flaugergues March 25 Battle of Anholt Denmark March 27 April 5 April 6 Buenos Aires May 14 Paraguay Battle of Albuera France Great Britain May 16 Portugal 1811 Great fire of Podil June 9 Kiev Ukraine July 5 Venezuela Amedeo Avogadro Italy July 11