What about all the towns with names that are Union or variants on Union (Uniondale, NY)? I always assumed that they were founded during or shortly after our Civil War. Have I been wrong, a victim of my own folk etymology.
Some predate the Civil War, e.g., Uniontown in Pennsylvania, and Union City on the border of Ohio and Indiana.
Belisarius: I’ve not got a clue what column you’re referring to… could you let me know so that we can provide a link?
Some have nothing to do with the Civil War. Union City, California was named because it was formed by uniting two unincorporated communities of Alameda County: Decoto and Alvarado.
<moderator> It must be that column. However, this is a tangent to itself. So I’m going to toss this one over to General Questions and make the title more descriptive. </mod>
Union College of NY – founded in 1795 and thus one of the earliest to use Union in its name – used the name because instead of being run by a church, it was a union of denominations: nondenominational. While other towns and cites were not named for it, the thinking was similar: two or more groups or towns would unite into one.
For some reason (probably because I am in the Uniondale/East Meadow/Garden City area quite often), I am compelled to mention that Uniondale, NY is neither a city nor a town nor a village, but rather just an unincorporated area within the Town of Hempstead (which the wiki article on Uniondale insists on calling a Hamlet, althought I don’t recall a lot of other people, actually nobody else, using that term - it’s just “Uniondale”) that has a rather flexible northern border, depending on whether the business perfers using Uniondale or East Garden City in it’s address.
Uniondale has a historical society :D, who may or may not be able to answer the OP’s question specifically for Uniondale, NY (no webpage I could find) - its up to the OP to find out the story for the hundreds of other “Union” municipalities through-out the nation
Uniondale Historical Society
540 Mitchell Street
Uniondale NY 11553
Ernest Catanese
ernestcat@juno.com <– Juno, baby! 
There’s a Union County in South Carolina, and the story I heard was that it was named after the Union Church, so named because it accepted people of all denominations, or something like that.
Union, MO was founded in 1825. According to the city, the name was chosen “to express the coming together of people and ideas as demonstrated by Union’s selection as the new, centrally located seat of county government in the early 1800s.”
I’ve encountered it elsewhere, in Tappan. I gather it’s the standard New York State technical term for something village-ish and unincorporated.
The Town of Union (which encompasses Johnson City and Endicott, NY - among other areas) was named Union becase it’s where the US Revolutionary armies combined in the Sullivan Campaign.
There’s an street named Union in Memphis, and its historical plaque claims that it is named for a local city merger rather than the Union of civil war fame.