Josiah Kirby Lilly, Jr. (1893-1966) was the youngest son of J.K. Lilly Sr. He earned a pharmacy degree from the University of Michigan and entered the family business in 1914. He focused on personnel and marketing. Largely through his efforts, Eli Lilly and Company became known for its “personnel-friendly” policies, such as fair wages, benefits for employees, etc. In 1944, J.K., Jr. left the vice-presidency to head the Eli Lilly International Corporation. He became president of Eli Lilly and Company four years later.

He held a great interest in rare books and manuscripts, amassing a large collection of items. His collection was donated to Indiana University in 1956-1957 and became the core of the Lilly Library, the rare book and manuscript repository on the IU-Bloomington campus. Material was also donated to the Indiana Historical Society. Josiah Kirby Lilly, Jr., born in 1893, collected things from the time he was a child, beginning with his movie theater ticket stubs. After finishing college in 1914, he joined the family firm of Eli Lilly and Co. He served in France in WWI where he continued to collect things. After the war he returned to work in the family business and succeeded his brother as president in 1948. Later he became chairman of the board; a position he held until he died.
He continued to work on his collections, amassing 20,000 books and 17,000 manuscripts which he gave to Indiana University. His gold coin collection, 6113 pieces, went to the Smithsonian. The J. K. Lilly, Jr. family residence, the National Historic Landmark Oldfields–Lilly House & Gardens, is on the grounds of the world-renowned Indianapolis Museum of Art. The Lilly House features eight furnished historic rooms on the main level. The majority of these rooms reflect the 1930s period of the Lilly family’s occupancy and almost 90 percent of the furnishings and decorative arts objects featured belonged to the Lillys and were used in the home. IMA’s gardens and grounds are renowned for their beauty, elegance and history. The 152-acre complex includes: Oldfields, the 26-acre American Country Place estate that once belonged to J.K. Lilly Jr.

In the Traders Point area, Mr. Lilly built rural recreational buildings and amassed large parcels that later became part of the 4,900 acre, municipally owned Eagle Creek reservoir and park. The Lilly family and others who created or modified the Traders Point area’s built environment during the 1930s to 1950s had accumulated wealth before the Great Depression, and their industries and investments were relatively unaffected by its financial disruption. The map above shows the land accumulation that Mr. Lilly and other successful people from Indianapolis had achieved by about 1935 near Traders Point, including the Eagle Creek Park area. Mr. Lilly put some of his land into farming and planted trees on the rest. However, he built only weekend or vacation lodges and outbuildings on the Traders Point area land, (including a now-demolished stable at the northwest corner of West 65th and Dandy Trail) , and retained his primary residence of Oldfields nearer to Indianapolis.

During Mr. Lilly’s ownership of land in the area, , Eagle Creek was inaccessible for public recreation, except by permission, for the simple reason that land was privately owned. No parks existed along Eagle Creek until the reservoir and Eagle Creek Park were created in 1968. The original settlement of Traders Point, which had flooded almost annually, was razed to create a spillway for Eagle Creek reservoir. In this map, circa 1935-1940, (above), the name of J. K. Lilly, Jr., as owner is attached to some 1,400 acres south of Traders Point. By 1941, when the land was sold or donated to Purdue University, Eagle Crest Estate (as Lilly called the landholding) included 3,600 acres. It was initially run as a farm, raising grain, soybeans, hay, and hogs, then registered beef and dairy cattle. Lilly made some of the parcels into a nature preserve that he planted with hardwood saplings and stocked with pheasants for hunting. Two rustic lodges with Tudor Revival details are located on 172 acres that Lilly purchased from a C. E. Parker in 1935; and a third, more substantial residence of similar style stands west of Eagle Creek. In spite of the buildings’ potentially early date circa 1910, they are included within the Traders Point’s estate-era period of significance 1925-1956. The building pictured above, the park’s Nature Center, was the 1930s storage space or library for collections owned by J. K. Lilly, Jr. This is believed to be the true birthplace of the esteemed Lilly Library on the IU campus in Bloomington. If J. K. Lilly, Jr., did not construct this building, he had it remodeled to safeguard his manuscript, coin, and other collections. There is a room-sized safe within the building’s interior, and all windows are fitted with pocket-type sheet-iron shutters that can be slid closed and locked. The center unit of the building has a recently remodeled room with large windows providing a view of the reservoir. (source: Eliza Steelwater, Author of United States Department of the Interior National Park Service National Register of Historic Places Multiple Property Documentation Form: Rural Historical and Architectural Resources of Eagle Township (Boone County) and Pike Township (Marion County), Indiana, 1820-1956, c. 2006.