1) The American Revolution
The relationship between French and American began right after the creation of the US: during the Independence War. American people asked the help of the French kingdom against the English because they knew the two of them had history. Actually, French people were just defeated by the English in what we now call the seven years war and so they wanted to take their revenge. But French were still ruled by a king at the time: Louis the Sixteenth. He wasn’t too keen in helping a country creating a democracy because he was afraid of the example that would create. So at first Louis the Sixteenth helped secretly by giving weapons to the American army. But some French people were really inspired by the fight American people started, and so without any command from their king decided to go to America and join the American army. Among those people, there was the famous general La Fayette. Then the three ambassador sent to France, among which was Benjamin Franklin, finely convinced Louis the Sixteenth to make his support to the American cause public and so France became the very first country to acknowledge the United States of America as an independent country.
2) The French Revolution
The relationship between France and America is not one-sided. The creation of the US inspired a lot of French people during the French Revolution. The American Declaration of the Right of Man directly influenced the French one because among the people who wrote it, some fought at the Independence War. Also the US showed people all over Europe that another system than Monarchy was possible.
3) The Statue of Liberty
One of the best examples of the friendship between America and France is of course the Statue of Liberty. It was given by French people to American people for the 100 years of the independence of the US. The sculptor, Frédéric Auguste Bartholdi, tried to represent the allegory of American freedom. The project can be considered a collaboration between America and France because the pedestal was made by the US.
To renew the friendship instituted by this gift, American people gave French people the light of the Statue of Liberty a 100 years later. It is now near the Alma Bridge in Paris.
4) World War I
During World War One America and France fought side by side. Even before the official declaration of War, a lot of American people wanted to fight with France against the Germans. After the declaration of war, the first ally of France was America. And so the first troops and supply were sent to France. Because none of the American soldiers understand French the army actually gave the soldiers sent in France some English/French dictionaries.
5) World War II
We remember now that French people fought with the Ally during World War II but actually most of France was under German occupation because the French government cooperated with the Nazis. French people were however among the victors at the end of the war because of the Resistance started in London by the general Charles de Gaulle. The Resistance is the one that came out of the war among the victors. The people of the resistance were the ones that fought with the American people during the Normandy landing and helped free Europe.
At the end of the War, the US created the Marshall Plan (or the European Recovery Program) to help Europe and so France as well. In France this was really helpful because most of the country was under the occupation and so suffered great damage during the liberation. Except Paris, of course, because St Genevieve is protecting us!