Fredericka Mandelbaum was born on March 25, 1825, in the central German city of Kassel. She settled in New York City in 1850 during the large, midcentury wave of German and Irish immigration to the United States. Mandelbaum arrived poor and, starting as a peddler, built a successful business as a criminal entrepreneur, the most noted “fence,” or receiver of stolen property, of her time, achieving success and fame from the 1860s through the early 1880s.