I know The Authorities (state-level government, I suppose?) allow multiple names (eg, first name John Jacob, middle Jingleheimer, last name Schmidt).
What if I want to change my name from Jane Doe to Megatron? Or, more reasonably, just Jane? I assume it varies state to state, and I’m not actually considering doing it, but I’m just curious as to whether or not it’s something that could be done.
Teller, of Penn and Teller fame, is legally named just “Teller.” He was born Raymond Teller, and legally changed it to simply Teller. In one of their books he claims to be “one of the few citizens” so officially named, which suggests he is aware that there are others.
Immigrants from other countries with different naming traditions might also have a single name. I’ve known a couple of different Indian students with a single (very long) name.
A friend in college had her name legally changed to just one name. We were all amused to find out that most government agencies required a last name but not a first name. The University had her officially had her listed as NFN Lastname. (NFN=no first name.)
It’s not unusual for Indonesians to have a single name. In fact, I once knew one Indonesian researcher who had a single name, and his scholarly research reports were routinely rejected by international journals for the sole reason that he did not supply a first and last name. So he made up a first (or was it a last?) name for himself, and everything was fine after that.
I had a Cameroonian friend with only one name (and a pretty short, common one at that- kind of the Cameroonian equivalent of “Dave”.) He occasionally had to travel in the US for work. He said he’d get a lot of trouble when he tried to get visas and the like. But it always worked out. So I’m guessing it is possible, just an occasional pain in the butt.
I know several women with only one name - all three of them were born here in the US and for various reasons decided to legally change their names to a name.
The only issue that I’ve seen it cause is they tend to get asked “No, what is your full name?” a lot. It also made things a little fun when our IT department was assigning their logon IDs since it’s based on first/middle/last initials.
I have another friend whose middle name is the peace symbol. That’s what his parents wanted to use and at the time, birth certificates were still handwritten so there it is. He tends to get a lot of stuff with “O” or “Q” as his middle initial.
We had an Indonesian grad student who had only one name and she was insistent that it was her only name and woe betide any professor who complained. The president of Indonesia was (maybe still is) Megawati, but when pressed she made it Megawati Sukarnoputri, pretty clearly a patronymic since Sukarno was her father. Icelanders normally have only one name (there are a few exceptions, mainly for families that had used last names before the law went into effect, although Vladimir Ashkenazy was another). The president was named Vigdis and so referred to by Icelanders, but for foreign consumption she used her patronymic Finnbogadottir. But Icelanders do this as a matter of course, when leaving Iceland, while apparently Indonesians don’t when they leave their country.
That said, nearly every online form I have ever seen will not permit a single name. So even if you call yourself Gastel Nofamilyname you will have to call yourself something.