Milan is an ancient city in northern Italy first settled in about 400 BC by Celtic Insubres. Milan fell under Austrian rule in the beginning of the 19th century and remained so until it rejoined the Kingdom of Italy in 1861. Milan experienced an economic boom after World War II. Milan became one of the world's fashion capitals during the 1980s with the success of Milanese fashion houses like Armani, Versace and Dolce & Gabbana. The city suffered from political scandal and financial crisis in the 1990s. Milan underwent an economic redevelopment in the early 21st century as well as a reversal of the decades long population decline.