On a driver's license in Aunt Marie's Book of Lore, it says his name was James Christopher Monroe. In the early casting call, his name was Eddie Monroe. Both of these names have been deemed false by the writers. I believe that he's a mononymous person; he probably changed his name in the past or something. Although, his parents (Bart and Alice) were not given surnames either, so there's a possibility that they have a really embarrassing surname like Dungworth, Schittemakker, or Krapp.
Silas has said adamantly in interviews that Monroe's name is not "Eddie" -- that was an early thing the writers later dropped. Monroe's own parents call him "Monroe". His mother's maiden name is Dietrich (as with Uncle Felix) but with all the goings-on about their deep German heritage, it'd be weird for Bart's surname to be Monroe (a name of Scottish origin) unless Bart's German side is from his mother? I suspect maybe the writers just didn't work all this through, leaving us to obsess about it! ;)
And yet -- on the ultrasound monitor when they discover there are triplets on the way, the "Patient Name" is displayed as Rosalee Calvert Monroe.
Wonder if there'll ever be a definitive answer? Perhaps we'll have to go with Roacher27's theory that he's mononymous, having changed his name or dropped part of it at some point, as Silas has said in interviews, "like Cher!"
I remember an episode of GRIMM where Nick introduces Monroe as "James Monroe." I don't even know which season it was, because at that time I was watching a daily showingof the synicated series on TNT. I didn't think his full name was a big deal, so I didn't record which episode it is. Now I wish I had, since there seems to be some misleading information being put out. If the writers are denying Monroe's first name is James, they are either forgetful, or they want to wish away the fact that their script clearly named him. Maybe they would like to wish away what they did, to make him seem more mysterious as a mononymous person. If they wanted that, they should have been more careful. Of course, without an episode citation my testimony will not be satisfying to many fans. But remember that cited license for "James Christopher Monroe." It fits right in. That is another name reference that I myself never noticed.
According to the transcripts I have available, James Monroe was never spoken in an episode (or even a webisode). Eddie Monroe was an early possibility in early drafts of the Pilot episode, but that was scrapped. When going over episodes of Grimm, I always tried to see if Monroe's name was revealed on documents, licenses, or anything that might have his name written down somewhere, but the writers and editors were very careful to either obscure where his full name would appear or crop it out of the shot. A good example of this was during the Season 6 episode "Breakfast in Bed," when Monroe checks into the Englewood Hotel.
Just following up on my last post and replying to the one above; I wish after the episode aired, I had asked the writers about how Rosalee's name appeared on her ultrasound, but despite that episode and appearance of her name (it's notable, however, there's no hyphen between Calvert and Monroe), the name Monroe has appeared in Grimm scripts as his first name and was confirmed early on by Silas Weir Mitchell himself to be his character's name (link for reference here: https://web.archive.org/web/20120707232423/http://blogcritics.org/video/article/grimms-silas-weir-mitchell-speaks/). The mystery of his last name became a bit of a running gag on the show, and I have a feeling the writers definitely teased the fans with it every so often... great example -- during Rosalee and Monroe's wedding ceremony, right as Judge Mason is about to reveal his last name ("I now present Mr. and Mrs...."), Trubel interrupts the wedding! There were other moments throughout the show where the camerawork cleverly obscured Monroe's last name on official documents as well. It's certainly not a coincidence that Monroe's parents, Alice and Bart, never had their last name revealed either, nor anyone on the paternal side of Monroe's family. (Even the NBCGrimm twitter account made reference to Monroe's unknown last name once: https://twitter.com/nbcgrimm/status/567379071592448000?lang=en) Come to think of Alice and Bart, it would be highly unusual for them to refer to their son by his last name. Think of Monroe as just a one-name moniker... like "Cher" or "Beyoncé" lol. I wish I could offer theories about Monroe's last name, but after reflecting on it, I like that it became kind of an inside joke.
In the scene where Rosalee finds out she is having triplets in Season 6 Episode 5: The Seven Year Itch, Rosalee's patient name on the moniter is 'Rosalee Calvert Monroe' leading me to belive that his last name is Monroe and Rosalee took his last name but kept hers as a middle, assuming she didn't already have one
18.104.22.168 wrote: In the scene where Rosalee finds out she is having triplets in Season 6 Episode 5: The Seven Year Itch, Rosalee's patient name on the moniter is 'Rosalee Calvert Monroe' leading me to belive that his last name is Monroe and Rosalee took his last name but kept hers as a middle, assuming she didn't already have one
See my previous post -- Monroe has been confirmed as his first name by the show and the actor himself, despite the ultrasound scene mentioned here.