As the only heir of the world's first billionaire, John D. Rockefeller Jr. always knew that he had some big shoes to fill. Often called "Junior" to distinguish him from his father, much of the younger Rockefeller’s working life was dedicated to finance and philanthropy. After graduating from Brown University, Junior joined his father's business in 1897, becoming a director of Standard Oil. Later, he also served as a director at J. P. Morgan's U.S. Steel company and was involved in the development of the vast office complex in Midtown Manhattan known as Rockefeller Center, making him one of the largest real estate holders in the city. By 1910, Junior was no longer interested in managing commercial interests, so he turned his focus to philanthropy. Historians estimate that during his lifetime, Junior gave away $537 million to a wide variety of different causes, including educational, religious, cultural, medical, and civic projects. Among his most notable projects was the reconstruction of Colonial Williamsburg in Virginia.
In September 1893, Junior entered Brown University, a school chosen for its connection to the Baptist Church. Unlike many scions of wealthy families, Junior was known for being remarkably meticulous with money. He used a ledger to write down all his expenses and was thrifty to the point of washing his own clothes over a Bunsen burner in his dorm room. At Brown, he also gained independence and confidence. Nicknamed "Johnny Rock" by his roommates, he joined both the Glee and Mandolin clubs, taught a Bible class, served as manager of the Brown football team, and was elected junior class president. He also joined the Alpha Delta Phi fraternity and was elected to Phi Beta Kappa. In 1897, after taking nearly a dozen courses in social sciences, including a study of Karl Marx's 'Das Kapital,' Junior graduated with a Bachelor of Arts.
Afterwards, Junior was devoted to Brown, which had offered an experience that shaped the rest of his life. At his 50th Class Reunion, Junior recalled his formative years on the Providence, Rhode Island campus: "Only here did I enjoy a completely independent personality... just one of a hundred others, but at least one who stood on his own feet... There has been nothing in my life since then quite like this." A year prior, Junior had already given a "substantial amount" to Brown for the construction of the Wriston Quadrangle on campus, and he later contributed an extra $5 million dollars in 1955. Brown recognized Junior's accomplishments multiple times, awarding the former student an honorary Master of Arts in 1914 during Brown’s sesquicentennial celebration and a Doctor of Laws in 1937, when he served as chief marshal at the first Commencement presided over by President Wriston. Junior was awarded the Rosenberger Medal in 1931 and a Brown Bear award in 1956. Four years after his death, Brown named one of its main libraries after Junior. Completed in 1964, The John D. Rockefeller Jr. Library is simply nicknamed "the Rock."