(I did do a search. It I couldn’t find anything)
“One day men will look back and say I gave birth to the twentieth century.”
A Ripper quote? I thought for sure this was in the famous From Hell letter. Reading wiki just now I see I was mistaken. Casting about on the internet I see there are various attributions including Jack himself but no actual cite that I can find. Can someone enlighten me?
Side note: they lost the freakin’ From Hell
Letter!? WTF?
That does not sound at all like an authentic quote to me, it sounds very much like a modern invention.
How could JtR have known what would happen in the 20th Century? A lucky guess?
It’s much too erudite to be consistent with the barely literate content of the From Hell letter. Maybe it’s from the graphic novel From Hell?
It’s from the movie From Hell.
Probably from the Alan Moore comic later adapted into the movie, then.
Yes, that’s true. But the scuttlebutt (speculation?) on the webs is that it has an earlier providence.
There were similar lines in the movie Time After Time:
That said, I didn’t find the quote the OP was looking for.
Since we have no clue as to who the “ripper” was, it is impossible to attribute a quote to him.
It was generally agreed by the police at the time, and by researchers today who aren’t pursuing some pet theory like “Queen Victoria was Jack the Ripper,” that all the correspondence signed “Jack the Ripper” was forged by journalists trying to keep up interest in the story, and that it’s highly probable that ALL of the correspondence was forged.
I just remembered; I think an FBI forensic expert who looked at the case in the 1970s and wrote the first thing that could be called a “profile” of JTR (it wasn’t called a profile at the time), and first referred to him as a “serial sexual murderer,” did say something along the lines that he “ushered in the 20th century,” but he was talking about the advancement of police work, not that he gave the world the crime of serial killing.
The version in the graphic novel is: "“It is beginning, Netley. Only just beginning. For better or worse, the twentieth century. I have delivered it.” Spoken by Sir William Gull as the Ripper to his coachman John Netley immediately after the climactic murder of Mary Kelly. See here.
As a supposed remark by the Ripper, it pretty clearly originates with Moore.
To be accurate, like a fair amount of the case documents, it was almost certainly stolen from the archives quite some time ago as a souvenir. Presumably by someone in the police.
Did they also forge the kidney that accompanied one of the notes? 
True, it probably wouldn’t have been that difficult to come up with a random kidney in those days.
Actually by the 1880s British murder rates were down to 1.5 ( per year per 100,000 inhabitants ) ( by the mid-20th down to 0.7 ), so probably not that easy as most people were attached to their kidneys.
And were one to say that unknown murders could happen in dark allies, well the Ripper’s crimes were instantly discovered and out-cried upon.
For comparison American murder rates were 1.2 = 1900,
4.9 = 1907,
9.7 = 1933
and is now 2015, a respectable 4.9.
But even there it was probably difficult to find a spare kidney.
Wiki English homicide rates 1857-1993 Modern UK Crime Stats
Sure we know who he was: he was Jack the Ripper.
(Yes, that’s tautological, but it’s also valid. Whoever did the murders also left or sent notes, as well as scribbled lines on nearby walls. Those are quotes “from” Jack the Ripper. The Great Pyramid was designed…by the guy who designed the Great Pyramid. There has to have been such a person; we just don’t know his name.)
The suspicion at the time was the From Hell letter was a prank by some medical students, who could easily acquire a human kidney. Certainly then, and probably even today, a medical student or mortician could probably get hold of a kidney without murdering anyone.
One theory is that Jack the Ripper may not have existed. He may have been invented by the newspapers. The murders attributed to him occurred but they were unconnected crimes committed by different people.
True in a limited technical sense, I suppose, but the same could be said about a number of classic writings. Starting with, say, the Bible.
I think the OP was looking for a quote from one of the few writings attributed to the killer or someone pretending to be him; close enough. Unfortunately, the answer seems to be “Alan Moore,” which is even more frightening.
As others have pointed out the ‘letter from Hell’ is considered a journalistic forgery by most experts on the case. And no, it wouldn’t be difficult at all for a resourceful journalist to acquire a human kidney. Paupers were dying all the time and certainly nobody would care about or keep track of their organs. A small bribe to a mortuary assistant and your business is done.
The letter fulfils the need felt by many since the murders took place to at least have something, anything, which connects to the anonymous killer. The only genuine article we have (or had, I’m not sure it still exists) that does connect to him is the piece torn from Catherine Eddowe’s apron stained with blood and left by the wall on which an anti-semitic diatribe had been written. (We have no evidence that the Ripper wrote the diatribe and it was erased almost immediately on the orders of Police Superintendent Thomas Arnold who feared that if left it could cause riots. It clearly didn’t occur to him to cover it up and leave a police guard on it but unfortunately this was typical of the police bungling concerning the case.)
For the reason above I’m sure that the so-called Ripper letter will always be part of the mythology surrounding the case. We all know on this board how difficult it is to dispel a myth.