Query: The Civil War had many effects after the war, what was the main effect for New Haven?
Context: (Winchester would continue to produce arms in New Haven until 2006, and many of the buildings that were a part of the Winchester plant are now a part of the Winchester Repeating Arms Company Historic District.) After the war, population grew and doubled by the start of the 20th century, most notably due to the influx of immigrants from southern Europe, particularly Italy. Today, roughly half the populations of East Haven, West Haven, and North Haven are Italian-American.