George Henry Peabody, who came from a line of merchants, bankers and professional men, had moved from Connecticut to Columbus, Georgia, where he ran a prosperous general store.

After attending private school in Columbus, young Peabody spent a few months at Deer Hill Institute in Danbury, Connecticut.

The Civil War, however, impoverished his family, and in 1866 they moved to Brooklyn, New York, and young Peabody went to work as an errand boy.

He also took part in the activities of the Reformed Church in Brooklyn Heights, where he met and became good friends with young investment banker Spencer Trask.

During the 1880s and 1890s this investment house took a leading part in financing electric lighting corporations, beet sugar and other industrial enterprises, and railroad construction in the western United States and Mexico.

In the early 1880s, he helped his close friend Edward M. Shepard organize the Young Men's Democratic Club of Brooklyn, took a part in the 1892 presidential campaign on behalf of Grover Cleveland, supported the Gold Democrats against William Jennings Bryan in 1896, then switched to more moderate monetary reform as a member of the executive committee of the Indianapolis Monetary Convention in 1897.

In June 1932, Franklin Delano Roosevelt, then Governor of New York, visited Peabody for advice and support in deciding to run for President of the United States.

A tall man, in later years he developed a mane of white hair, and wore a heavy mustache and pointed beard, becoming known for his dignified and courtly manner.

Peabody continued to live on the estate, and in 1926, he adopted a daughter, Mrs. Marjorie P. Waite, a young woman whom he had come to know in connection with his civic and humanitarian activities and who aided him in them.