While most residents were evicted in the late 1920s for the construction of Floyd Bennett Field, some were permitted to stay until 1942, when the airfield was expanded as a wartime base of the United States Navy.

The water from the melting glacier ran downhill toward a low-lying delta that adjoined the Atlantic Ocean, which later became Jamaica Bay.

[2][10] From the mid-19th century, Rockaway Beach was extended more than one mile (1.6 km) to the southwest after several jetties were built to protect manmade developments there.

[10] This caused changes to Barren Island's ecology,[8] because during the early 20th century, it had contained sand dunes on the coasts and salt marshes inland.

[8] By the late 1920s, industrial development on Barren Island's eastern side had transformed that area, with a small patch of dunes remaining.

[17] In 1636, as New Netherland was expanding outward from present-day Manhattan, Dutch settlers founded the town of Achtervelt (later Amersfoort) and purchased 15,000 acres (6,100 ha) around Jamaica Bay north of Barren Island.

Moore characterized the island as "vacant and unoccupied" in 1762,[4] and it remained as such until the end of that century, being used mainly as a grazing field.

[4] Circa 1800, a man named Nicholas Dooley established an inn and entertainment venue for fishermen and hunters on the east side of Barren Island;[5][9][25] the house's ownership later passed to the Johnson family.

[26] The National Park Service states that the pirate Charles Gibbs buried Mexican silver on the island c. 1830.

[32] Few industrial sectors were enticed to move to Barren Island, precisely because of its isolation: there were no direct land routes to the rest of the city.

[33][39] A factory belonging to the Products Manufacturing Company, located where Flatbush Avenue is now, was reportedly the world's largest carcass-processing plant.

[39] Barren Island's factories, which were vulnerable to landslides, fires, or waves from high-tide, typically lasted for fleeting periods of time.

[39] A subsequent census in 1880 counted six households that were entirely composed of single men, as well as 17 families,[41][43] and found that 309 people resided on the island.

[47] There had been a steep decline in the number of menhaden off Long Island by the late 1890s, which, combined with the Panic of 1893, resulted in the closure of the fish-oil plants.

[54] Barren Island soon became known for its use as a garbage dump, receiving waste and animal carcasses from Brooklyn, Manhattan, and the Bronx.

[20] The Sanitary Utilization Company disposed of glass bottles and other non-processable items on the northern coast of Barren Island.

[63] Barren Island served as a residential community for the families of laborers who worked there, and at its peak in the 1910s, it was home to an estimated 1,500 people.

[37] The island had a public school, a church, a post office, a New York City Police Department precinct, hotels and inns, various stores and saloons, and three ferry routes to other Brooklyn neighborhoods.

[61][63] A "Main Street" stretched east–west across Barren Island, lined with buildings that faced south toward Rockaway Inlet.

The street grid in the island's central section was built haphazardly, based possibly on sand dune patterns.

[63] A caste system divided the different types of workers on the island: "rag pickers" were at the bottom of the hierarchy, followed by metal-and-paper scavengers, then bone sorters.

[69] Hylan ultimately won the election against Mitchel, and he threatened to revoke the Fresh Kills landfill operator's license.

[67] The city government started dumping its trash into the ocean in 1919, and the Sanitary Utilization Company closed its facility two years later.

[70] The last garbage processing plant on Barren Island, the Products Manufacturing Company, was transferred to city ownership in 1933, and operations ceased two years later.

Residents of "mainland" Brooklyn could go to the Rockaway beaches by driving to the end of Barren Island and taking the ferry.

That plot was combined with a 110-acre (45 ha) tract owned by Kings County to create a public space called Marine Park.

[15] A contract for the airport's construction, awarded in May 1928, entailed filling in or leveling 4,450,000 cubic yards (3,400,000 m3) of soil across a 350-acre (140 ha) parcel.

[56][61][70] In 1935, the city acquired 1,822 acres (737 ha), including the entire island west of Flatbush Avenue, for Robert Moses's expansion of Marine Park.

[70][90][91] During its wartime upgrade of Bennett Field, the Navy burned and cleared all remaining structures on Barren Island, and eliminated its original landscape.

[95][96] In August 2020, the National Park Service announced that Dead Horse Bay would be closed indefinitely because of the presence of radiological contamination.