This page contains information specific to New Jersey. For additional information about the project, please see also the project About page.
It is believed that municipal formation records after 1800 are complete, and that annexations after 1800 are over 90% complete.
Special thanks to the New Jersey Geological and Water Survey for permission to incorporate data from Bulletin 67, written by John P. Snyder, in this resource.
The tables in the New Jersey Geological and Water Survey's Bulletin 67, written by John P. Snyder, were converted into database tables, and were then reformatted into a standardized format both for citation purposes and separately to act as the basis of the geohistory event records. Titles, page numbers, and dates of most of the cited laws were abstracted. In addition to reviewing the material in the bulletin, historical state codes were examined to determine the legal procedures and the agencies involved in such matters. A comprehensive review of indexes to the Secretary of State's Statutory/Miscellaneous Filing series, including from the State Archives's card catalog, the State Archives's electronic index, and the Secretary of State's electronic index, was completed. The previous year's index is continually requested on an annual basis to locate new filings. Every identified non-map instrument was examined and photographed. Separate Secretary of State County and Municipal Filings were also examined. A review of county record inventories, mostly from the late 1970s or early 1980s, at the State Archives was done to determine which counties had the municipal incorporation record books specified in N.J.S.A. 40:43-2. In several counties, such books that existed in inventories were unavailable; in at least one other county, a such book was located but was completely blank. Fewer than half of the total counties were determined to currently have books clearly qualifying, although some of the remaining counties had such instruments scattered among other books or docket boxes. In some counties, other types of record books at the County Clerk, such as partition books, division books, road books, incorporation books, miscellaneous books, street vacation books, or general deed indexes, were also examined in part.
Additional information concerning government form not addressed by Snyder's work has been incorporated. Older state incorporation date publications were referenced for information on the adoption of Commmissioner and Municipal Manager forms of government. County and Municipal Government Study Commission records at the State Archives were consulted for information about proceedings under the Optional Municipal Charter Law, and records from the Department of Community Affairs concerning the current classification of municipalities were obtained. Charter commission reports at the State Library and, in limited cases, at local libraries, were consulted.
A 2013 vintage of NJGIN's Municipal Boundaries GIS layer was used to create the initial GIS base layer. This source relied heavily on data from tax parcel maps and GIS features, and is consistently highly accurate throughout the state. U.S. Census Bureau TIGER/Line Shapefiles were additionally used to determine state and county lines in the Delaware Bay and the Atlantic Ocean where state data did not recognize the territory to be divided into municipalities. Efforts have been made to conflate data to match the 2019 vintages where the latter are more accurate or precise. Multipolygon features were split into polygon features, and data was converted to WGS 84 (EPSG:4326). Mapping boundary changes is only in preliminary stages. In order to show changes in boundaries, features were further split into "areas" that share a common jurisdictional history, taken both from Snyder and boundary legal descriptions. In some cases, minor adjustments derived from alternate sources were made to municipal boundaries, some of which were the result of minor boundary changes not yet captured in state data. Most of these adjustments were made after reviewing maps and primary source records described above in conjunction with other modern sources, such as municipal tax maps.