Are there records for people who changed their names in New York City (NYC) in the 1830's?
My ancestor was from France and changed his name after arriving in NYC in the 1830's.
For an overview and timeline for New York Law, see the New York State Archives' research guide Naturalization and Related Records: Records of Name Changes.
If you're looking for a formal legal document such as we might have in the 20th century, declaring the 'old name' and 'new name' of an immigrant, you may not find one for this period, especially if you are looking for online computer databases with 'name change' or 'changes of name' in the title itself. Some records documenting name changes do survive, such as these collections/databases at Ancestry:
But if you don't find a collection like these in your favorite online site, don't stop looking. Evidence of the name change may exist in other records offline, or be revealed when you look at other historical records.
Why these records can be difficult to find:
The United States follows the common law, where it is okay to change your name as long as you aren't doing it for fraudulent intent -- all you have to do is begin using the new name.
In her essay on Immigrant Name Changes, Marian L. Smith writes:
The documentation of name changes during US naturalization procedure has only been required since 1906. Prior to that time, only those immigrants who went to court and had their name officially changed and recorded left us any record. Congress wrote the requirement in 1906 because of the well-known fact that immigrants DID change their names, and tended to do so within the first 5 years after arrival. Without any record, immigrants and their descendants are left to construct their own explanations of a name change.
So if your ancestor did change his name, where else besides naturalization papers could the information have been recorded?
Name change documents which are in the courts are likely to be 'hidden' in collections of miscellaneous records like this one at FamilySearch.org:
Microfilm of records in the New York County Courthouse.
Alphabetical list of records in the office of clerk of the County Court, New York County.
Includes marriages ca. 1832-1851, court records, personal name changes, partnership, incorporations, trade marks, and etc.
These are images of index cards. The collection consists of 17 microfilm rolls (see the film notes in the catalog for an alphabetical breakdown). The film has been digitized and can be browsed (it isn't searchable). If you find your person's index card, you'd have to contact the clerk of the County Court for New York County to ask if you can get copies of the original records.
The FamilySearch Wiki article New York Names, Personal suggests using this guide:
Kronman, Barbara. The Guide to New York City Public Records, Fourth Edition. New York, New York: Public Interest Clearinghouse, 1992. (Family History Library book 974.71 A3k.) Includes chapters on city government, courts, libraries, and personal information. Shows how to obtain vital records, name change records, and naturalizations.
The National Genealogical Society offers this publication of compiled records:
Petitions for Name Changes in New York City, 1848-1899. Compiled by Dr. Kenneth Scott, FNGS. All genealogical data pertaining to legal name changes in New York City between 1848 and 1899. Indexed. 1984. 144 pp. Hardbound. NGS
To find private laws (where a bill might be passed to change someone's name) and to find out what the rules are for a legal name change (a "public law") for that period, you could search here: Laws of New York State: Digital Collections at the New York State Library or Laws of the State of New York at Manhattan Past. (Thanks to Judy G. Russell for these links, via the handout for her lecture, "The Private Laws of the Federal and State Governments", given at Legacy Family Tree Webinars.)
Other places to search:
If you can't find your ancestor in the legislative record or in court documents like the collections linked to above, you might be able to find some trace of a name change in the ordinary records that people leave behind -- in newspapers and magazines, or anywhere that someone writing about your ancestor might have needed to include a 'formerly known as' statement in order to clarify which person was being talked about.
Don't forget the usual suspects -- Google Books, Hathi Trust, and the Internet Archive -- to find works like List of Persons Whose Names Have Been Changed in Massachusetts. 1780-1892 which is the original source for the Ancestry database linked to at the top of this answer. (Thanks go to Christine McCloud for the pointer to the original book.)
In New York City especially, where you might have many people with the same name living close to each other, I would expect people to find some way to distinguish themselves from each other, such as the use of middle initials, a dit name, or some other kind of descriptor.
These resources don't specifically refer to New York City but may be of interest for putting records in context:
Other guides and finding aids:
All of these are available in the shop of the New York Genealogical & Biographical Society -- or you can try a search in WorldCat to find any of the books mentioned here in a library near you.