1682 René-Robert Cavelier, Sieur de La Salle, claims for France all territory drained by Mississippi River from Canada to Gulf of Mexico and names it Louisiana.
1718 New Orleans is founded.
1762 France cedes New Orleans and Louisiana west of the Mississippi to Spain.
1763 France cedes territories east of the Mississippi and north of New Orleans to Britain.
1783 Treaty of Paris gives newly independent United States free access to the Mississippi.
1784 Spain closes lower Mississippi and New Orleans to foreigners.
1789 French Revolution begins.
1790 Slaves revolt on Caribbean island of Saint Domingue, France's richest colony.
1795 Spain reopens the Mississippi and New Orleans to Americans.
1799 Napoleon Bonaparte seizes power in France.
1800 Spain secretly agrees to return Louisiana to France in exchange for Eturia, a small kingdom in [[Italy]].
1801 President Jefferson names Robert Livingston minister to France.
1802 Spain cedes Louisiana to France. New Orleans is closed to American shipping. French army sent to re-establish control in Saint Domingue is decimated.
January Jefferson sends James Monroe to join Livingston in France.
February Napoleon decides against sending more troops to Saint Domingue and instead orders forces to sail to New Orleans.
March Napoleon cancels military expedition to Louisiana.
April 11 Foreign Minister Talleyrand tells Livingston that France is willing to sell all of Louisiana.
April 12 Monroe arrives in Paris and joins Livingston in negotiations with Finance Minister Barbé-Marbois.
April 30 Monroe, Livingston, and Barbé-Marbois agree on terms of sale: $15 million for approximately. 827,000 square miles of territory.
May 18 Britain declares war on France.
July 4 Purchase is officially announced in United States. October 20 U.S. Senate ratifies purchase treaty.
November 30 Spain formally transfers Louisiana to France.
December 20 France formally transfers Louisiana to United States.
December 30 United States takes formal possession of Louisiana.