An aerial view of Manhattan in 1873, with Battery Park in the foreground and the Brooklyn Bridge under construction at the right. After the American Civil War concluded in 1865, New York saw an influx in immigration from European countries looking for a new life in the United States. However, the squalid conditions and low wages allowed these immigrant communities to become hotbeds of revolutionary ideas.Engraving: George Schlegel; restoration: Adam Cuerden