The 1st of November is la Toussaint in France, or "All Saints' day". It's the day when French people commemorate their dead. It's a catholic celebration but as it is a public holiday, most people in France take the opportunity to go to the cemetery. They buy chrysanthemum flowers to put on the grave and light candles to symbolise a happy life after death.
The name comes from "tous les saints" as the celebration is dedicated to all saints.
Since the end of the 1990's, French people celebrate Halloween on the eve of la Toussaint too. It's become more and more popular since then.