For those living in the New York City (NYC) metropolitan area (i.e., the five boroughs of NYC, Long Island, parts of northeast New Jersey, parts of western Connecticut and the Lower Hudson Valley), a reference made about "Brooklyn" is inherently different from a reference to "Long Island" - locals do not use the terms interchangeably.
It might, therefore, be a little surprising to learn that, early in 1936, the Brooklyn Chamber of Commerce (established in 1918) sent a petition to Congress (via the House of Representatives) that pledged its support for - and encouraged the passing of - the House bill that called for the striking of half dollar coins to commemorate the Long Island Tercentenary.
Why the support? I can think of at least two reasons:
1) The Borough of Brooklyn is technically - and geographically - a part of Long Island (its westernmost region). Nassau County and Suffolk County make up the balance/eastern portion of the island.
2) The settlement of Long Island has strong roots in Brooklyn.
The areas that today comprise Brooklyn were originally settled by Native Americans thousands of years before the arrival of Europeans. The Dutch arrived in the early 1600s, and purchased tracts of land from the indigenous people, often the Lenni Lenape, that included areas in what would become the NYC Boroughs of Manhattan and Brooklyn. The early Dutch settlers built homes/farms and established towns/villages on the acquired lands.
"Breuckelen" - named after the Dutch town of Breukelen - was one such early town. The town was chartered in 1646, grew and became a thriving port, was incorporated as a village in 1816, was incorporated as a city in 1834 and, ultimately, expanded/developed into what has become the present-day Borough of Brooklyn (following its annexation of surrounding towns/areas in 1894).
Note: The British seized control of Brooklyn/Long Island in 1664.From its western beginnings (largely under Dutch control), European settlement of Long Island expanded eastward to cover the balance of the island; the period of significant eastern expansion came initially while the area was under British control, but later while it was part of New York State within the United States (post-1776).
The Native American / Dutch link to the area was commemorated on the obverse of the 1936 Long Island Tercentenary Half Dollar with its conjoined portraits of a Dutch settler and a Native American.
1936 Long Island Tercentenary Half Dollar
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As the Long Island Tercentenary Committee (the half dollar's sponsor) was based in Brooklyn, the Chamber's actions were likely in support of a local business - an objective of most any Chamber of Commerce. But, it also helped draw attention to Brooklyn and its role in Long Island's history - a savvy way to "get in on the action" of Long Island's major anniversary!
For a brief story about commemorating a Revolutionary War-era Brooklyn, see:
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What If? Phantom 1928 Brooklyn Bridge Plaza / Battle Of Long IslandFor more of my posts about commemorative coins and medals, including other Long Island half dollar stories, see:
Commems Collection.