The greater St. Louis metropolitan area is home to nine Fortune 500 companies, as well as an advanced medical industry. This attracts many educated immigrants looking for jobs in these fields. The average quality of living in St. Louis is also very high compared to most large metro areas. These facts combined with St. Louis' push to make the city more immigrant friendly, and to bring in more immigrants each year, makes St. Louis a focal city for immigration and diversity.

The city of St. Louis has a rather large European, Latin American, and Asian ethnic make up. Throughout the history of the city, the European immigrants were primarily from Eastern European countries such as Italy, France, and Germany. However, there has been a recent influx of Bosnian refugees into the greater St. Louis area. Now the Bosnian people are one the largest people groups in the city, and St. Louis boasts the largest Bosnian population outside of their home country.

The Asian population has also skyrocketed in recent years. Due to the city's advanced medical and bioscience industries, many educated immigrants from south and east Asian countries such as China, Korea, and India, have been arriving in the city looking for jobs within these fields. If the immigration trends continue in this fashion, St. Louis could soon have one of the largest percentages of Asian population in the country.