Marseille lost a significant portion of its population during the Great Plague of Marseille in 1720, but the population had recovered by mid-century. In 1792, the city became a focal point of the French Revolution and though France's national anthem was born in Strasbourg, it was first sung in Paris by volunteers from Marseille, hence the name the crowd gave it: "La Marseillaise". The Industrial Revolution and establishment of the French Empire during the 19th century allowed for further expansion of the city, although it was occupied by the German Wehrmacht in November 1942 and subsequently heavily damaged during World War II. The city has since become a major center for immigrant communities from former French colonies, such as French Algeria.