Around 70 B.C., Nantes was firstly a town founded by the Celtic tribe named Namnetes.  It was conquered by Julius Caesar in 56 B.C. and named Portus Namnetus.  Nantes was successively invaded by the Saxons around 285, the Franks around 500, the Britons in the 6th and 7th centuries, and the Normans in 843.  And in 937, Alain Barbe-Torte, grandson of the last kind of Brittany who was expelled by the Normans, drove them away and founded the duchy of Brittany.

When the duchy of Brittany was annexed by the kingdom of France in 1532, Nantes kept the parliament of Brittany for a few years, before it was moved to Rennes.  In 1598, King Henry IV of France signed here the Edict of Nantes which granted Protestants rights to their religion.

Nantes was the slave trade capital of France during the 18th century, prior the abolition of slavery.  This trade caused Nantes to become the first port in France and a wealthy city.  Nantes chose to be part of it, although the whole surrounding region soon degenerated in an open civil war against the new republic when the French Revolution broke out.  

In the 19th century, Nantes became an industrial city. The omnibus service was initiated in Nantes in 1826.  Soon it was being imitated in Paris, London and New York.  In 1851, the first railroads were built and many industries were created. 

The city was occupied by the German troops in 1940.  And in 1941, the murder of a German colonel caused the retaliatory execution of 48 hostages.  Later in 1943, the city was bombed twice by British and American airplanes.  Nantes was freed by the Americans in 1944.  And after the World War II, the city slowly lost its industries.  The harbour was moved at the very mouth of the Loire river, in Saint-Nazaire.  It is only in the last 15 years of the 20th century that the city was able to move into a more modern economy.