How did immigration change the languages spoken in Brussels?

Immigration has played a fundamental role in the linguistic evolution of Brussels, transforming it from a historically Flemish-speaking city into a predominantly French-speaking one.12

During the 19th century, the city experienced an influx of newcomers from Flanders and Wallonia. While the Flemish arrivals generally occupied lower-status social positions, the Walloon immigrants were largely middle-class employees and civil servants. Due to the social prestige associated with the French language and significant social pressure, French became the dominant language for a large majority of the population by the mid-20th century.1

In the post-World War II era, economic expansion led to further immigration from Mediterranean countries, such as Italy, Spain, Greece, Morocco, and Turkey, as well as from the Democratic Republic of the Congo. Additionally, the establishment of EU institutions brought a large international population to the city. Today, while Brussels remains officially bilingual, French serves as the lingua franca, and English has surpassed Flemish as the most common second language.13