St. Louis is one of the great historic metropolises of USA which were developed in the 19th century while gradually settling the Western plains of American continent.
Mississippi river which straddles the city served as a premodern freight highway. Industry developed along it attracting European migrants, including Lithuanians.
Church of Immaculate Conception at East St. Louis (1509 Baugh Ave) is one of the best examples of Lithuanian-American national romantic architecture. It has been designed by Jonas Mulokas, its interior was created by V. K. Jonynas. Together these two authors created the post-WW2 style of Lithuanian churches where they sought to represent their lost homeland as best as they could (after all the post-WW2 migrants have been forced from their country by Soviets rather than emigrating on their own will).
The forms of the church aren't resembling any single historical style but they are not modern either. Even the Christian church elements have been "ethnicized" here: the cross is mixed in form with sun and moon (inspired by peasant or even pagan Lithuanian symbolism), windows are formed as crosses of Vytis while the tower is inspired by Baroque although not copying it directly (this is symbollic as at the time Baroque was regarded to be the most Lithuanian of Western styles due to its prevalence in Vilnius church architecture). East St. Louis Immaculate Conception church looks is similar to the All Saints Lithuanian church in Chicago and also has similar elements to the Nativity BVM church of Chicago (all three have been created by the same tandem of architects/designers/sculptors and had even a master thesis dedicated to them in Kaunas university). Lithuanian mass is still held here every Sunday.
Further east the suburb of Collinsville has a small white church built by Lithuanian Lutherans in 1903, known as the Jerusalem Lutheran church (305 Collinsville Ave). It is still open although no longer Lithuanian. It has been also organized by the victims of Russian occupation but the earlier Imperial (1795-1915) rather than the Soviet one (1940-1990). The pastor who established this church previously worked as book smuggler in Lithuania, importing Lithuanian books into Russian-occupied Lithuania at the time the Russian regime banned Lithuanian language.
St. Louis metropolis straddles accross two states as the Missouri/Illinois borderline here follows the Mississippi river. Both the aforementioned Lithuanian communities are located on the Illinois side but the Missouri side (which also has the St. Louis downtown) also had its own Lithuanian church dedicated to St. Joseph, built in 1915 in the historic Lafayette Square district famous for its turn-of-the-century architecture (address: corner of Park Avenue and MacKay Place). Small, looking as if built of stones, the church has been closed in 1970 when Lithuanians left the then-poor neighborhood.