Flatbush was originally chartered as the Dutch Nieuw Nederland colony town of Midwout (or Midwoud or Medwoud) — from the Dutch words, med, "middle" and woud, "wood" — in 1651. Both names were used in the Dutch era, and Midwood was an alternative name for Flatbush into the early 20th century. In a reversal, Midwood, now the area immediately south of Brooklyn College, is often alternatively called "Flatbush," especially among Orthodox Jews. Midwood's residents predominately feature a mix of the latter and Irish Americans.
Flatbush and the five other towns of what was to become Kings County, were surrendered to the English in 1664. The town was the county seat for Kings County and was a center of life for what is now called Brooklyn. The compact center of the village of Flatbush was at the intersection of what are now Flatbush and Church avenues, where we still find an old Dutch Reformed Church and Erasmus Hall, the oldest high school in New York City.
Flatbush played a key role in the American Revolution. Flatbush was where significant skirmishes and battles of the Battle of Long Island took place. As Kings County was settled largely by the Dutch, and as the Dutch were prominent in the slave trade, the area was somewhat sympathetic to the British side of the American Revolutionary War at the beginning of the conflict. Kings County at the time had the highest concentration of slaves north of the Mason–Dixon line – almost one-third of the total population for the county were slaves. When a Loyalist Governor of Virginia supported freedom for slaves who supported and fought on the British side, landowners in Brooklyn were concerned that a full conflict between the Colonies and the British would result in loss of their critical source of labor. Loyalist residents of Flatbush included David Mathews, Mayor of New York City, who lived at what is now the intersection of Flatbush and Parkside avenues. Flatbush residents maintained their loyalist sympathies: the King's Arms, for example, appeared in the town's inn for a half-century after the conclusion of the conflict.
The influence of Dutch merchant and farming families remained strong in the area until after consolidation into the City of Greater New York in 1898, after which the development of Flatbush as a suburb, and then an integral part of the larger city, proceeded apace.
Before it was incorporated into the City of Brooklyn in 1894, Flatbush described both the Town of Flatbush, incorporating a large swath of central Kings County extending east to the Queens County border, and the Village of Flatbush, formerly the heart of the current community. Many of the remaining early Dutch structures are in the Flatlands and Marine Park neighborhoods.
Flatbush maintained a kind of distance from the rest of Brooklyn and New York, but the emergence of the subway in the 1920s connected it to surrounding areas in an unprecedented way.
In the first half of the 20th century, Flatbush had a sizable population of Irish-Americans, Italian-Americans and Jews. Much as it is today, it was a working-class neighborhood. A significant portion of Flatbush residents closely followed the Brooklyn Dodgers, which at the time were not only the team of Brooklyn but also of Flatbush in particular. Dodgers centerfielder Duke Snider was known as "the Duke of Flatbush". By 1958, however, the Dodgers left Brooklyn, and Ebbets Field eventually was torn down. Due to shifting neighborhood boundaries, Ebbets Field today technically would be in Crown Heights, as the ballpark was located just north of Empire Boulevard.
During the 1970s and early 1980s, Flatbush experienced a shift in demographics as it went from being a mostly Irish, Italian and Jewish community to a mostly Caribbean community. While most sections of Flatbush were working class before the demographic shift, there were a few affluent areas. Prospect Park South had a sizable number of more affluent homeowners, and more than a few doctors resided on a stretch of Parkside Avenue immediately adjacent to Prospect Park. By the mid-1980s, however, there were a number of abandoned or semi-abandoned buildings in the community, with a number of apartment houses falling into a state of disrepair. While crime generally had always been a problem in the community it was particularly bad during the 1970s, '80s and '90s. A number of stores on Flatbush and Church Avenues had been looted during the 1977 blackout, and a drug epidemic ravaged Flatbush during the 1980s and early 1990s.
In February 2016, Flatbush was one of four neighborhoods featured in an article in The New York Times about "New York’s Next Hot Neighborhoods". After the Vision Zero initiative was implemented across the city, WNYC found the NYPD targeting this neighborhood 36 percent more than other whiter neighborhoods like Williamsburg and Greenpoint.