An isonymic study of the population structure of early Kings County, NY

Isonymy has proven a useful method for studying the genetic structure of historical populations. In the United States, the populations studied have been of predominantly British origin. Many of the early settlers in this country, however, came from different cultural backgrounds, which may have affected their settlement patterns and genetic structure. The first European settlers of Kings County, New York, were Dutch, and Dutch was still spoken there in the 19th century. In the early Colonial period, it was an isolated agricultural area, but it was increasingly drawn into the larger metropolis of New York City, a process that culminated at the end of the 19th century. This paper uses census data from 1698, 1738, 1790, and 1810 to assess synchronic and diachronic isonymy patterns within the county. These censuses subdivide the county into six towns, five founded by the Dutch (Brooklyn, Bushwick, Flatbush, Flatlands, and New Utrecht) and one by the English (Gravesend). All were founded at least a generation before 1698. Values of Iii, FST, and RST increased from 1698 to 1738, a period when Kings County received few immigrants, and decreased thereafter as the influence of the metropolis grew. Most new immigrants settled in Brooklyn, so the lowest levels of isonymy occurred there [Iii (1810) = 0.0029]. The highest levels occurred in Flatlands [Iii (1738) = 0.0838]. FST increased from 0.0050 to 0.0076, and then fell to 0.0052 and 0.0032; RST was approximately two-thirds as high, at 0.0033, 0.0053, 0.0033, and 0.0022. These values are more than twice as high as those reported from 19th-century Massachusetts or Pennsylvania, and are comparable to those found in rural European populations. The towns can be divided into two groups: Brooklyn, Bushwick, and Flatbush, with an average Iii of 0.01570, and Flatlands, Gravesend, and New Utrecht, with an average value of 0.03963. The three latter towns were geographically more distant from New York City and remained more isolated both culturally and biologically.