In the first half of the 20th century, while most of Trenton was segregated or defined by distinct ethnic neighborhoods, North Trenton was one of the few sections of the city where blacks, and whites of all ethnic backgrounds, lived together. North Trenton was regarded as a middle-class 'melting pot' peopled by a vibrant professional class which formed an important economic and cultural foundation for the city. After World War One, North Trenton became a magnet for Polish and Sicilian immigrants. It simultaneously attracted a thriving African-American middle class. The northernmost end of Brunswick Avenue became the heart of a 'Little Poland' district, while Italian neighborhoods emerged just north of the Battle Monument. Spring Street and Pennington Avenue formed the core of a thriving African-American community made up of black professionals who formed a distinct middle-class community unique for that time. North Trenton's diverse catalog of residents also included Russians, Middle-Easterners, Jews, and Anglos of English and Scottish descent. In 1939, a government study recognized North Trenton as one of the most successful and harmonious 'integrated' urban areas in the country, and designated it as a 'model' of economic and social vitality.