Prints historian; Curator and founder of the Prints Department at the Metropolitan Museum Art. Ivins' father was a prominent New York utilities lawyer, William Mills Ivins, sr., (1851-1915). The younger Ivins graduated from Harvard University in the class of 1901. After a year of study at the University in Munich, he attended Columbia Law School where he received his law degree in 1907. He was admitted to the bar and practiced law for nine years. In 1916 Ivins was asked by the Metropolitan to take charge of what was then a relatively small collections of prints.

Philanthropist and benefactor of the arts; nephew of art historian Aby M. Warburg; briefly taught art history at Bryn Mawr. Warburg was the youngest of five children of philanthropist Felix Warbug (1871-1937), a partner in the investment firm of Kuhn, Loeb & Company and brother of the German art historian Aby M. Warburg. His mother was Frieda Schiff (Warburg) (1876-1958), the only daughter of merchant banker and financier Jacob H. Schiff (1847-1920).