What Happened in 1818 — Events, Births & Deaths

The British Institution of Civil Engineers is founded by a group of six engineers; Thomas Telford would later become its first president.

Jean-Baptiste Bernadotte ascends to the thrones of Sweden and Norway.

Bernardo O'Higgins formally approves the Chilean Declaration of Independence near Concepción, Chile.

Physicist Augustin Fresnel reads a memoir on optical rotation to the French Academy of Sciences, reporting that when polarized light is "depolarized" by a Fresnel rhomb, its properties are preserved in any subsequent passage through an optically-rotating crystal or liquid.

In the Battle of Maipú, Chile's independence movement, led by Bernardo O'Higgins and José de San Martín, win a decisive victory over Spain, leaving 2,000 Spaniards and 1,000 Chilean patriots dead.

French physicist Augustin Fresnel signs his preliminary "Note on the Theory of Diffraction" (deposited on the following day). The document ends with what we now call the Fresnel integrals.

The Convention of 1818 is signed between the United States and the United Kingdom, which settles the Canada–United States border on the 49th parallel for most of its length.

Cyril VI of Constantinople resigns from his position as Ecumenical Patriarch under pressure from the Ottoman Empire.