Who was the courier that cancelled the job of the chip? It may have been explained somewhere, but haven't come across it. It's about the dialog from Johnson Nash in Primm:

-Do you know who he was? Where he went?
-No idea. Sounds like you two had a history for him to act like that. And turn down the money, too
-He canceled?
-Yeah, got this look when he saw you next down on the Courier list. His expression turned right around, asked me if your name was for real.
I said, sure as lack of rain, you were still kicking.Then he turned down the job, just like that. I asked if he was sure, it was good money.

there is a dlc about that cat, its called lonesome road. Actually all the dlc deal with the other courier and his wacky misadventures

Ulysses

All questions are answered in the lonesome road dlc.

He was originally going to be a companion in the base game, but because of time constraints they didn't get him incorporated in time.
So with the dlc they sort of rewrote his original concept and made him relevant to all of the dlc story arc

so do you think the shack at the south side of goodsprings "Victor's Shack" would have been his house if he was a companion? Thats what i assume since they said Victors old owner lived there, and with the flag and everything I assumed that was his shack you could recruit him from, Victor was his robot that was taken over by Mr House, etc and the shack abandoned and more backstory put in when he was put in the DLC instead of a companion.

I thought he was gonna live at Wolfhorn Ranch

this is his house

http://fallout.wikia.com/wiki/Wolfhorn_Ranch

If you want to know the story of the first Courier, play all the DLC's. Lonesome Road is merely the climix. He has an influence in practically everything that happens in the New Vegas story.

Well Wolfhorn ranch was "A" house of Ulysses, he was about the area as a Legion spy/scout/etc for a long time. His time at the ranch he was posing as a Ranch Herder, but he's been about many other places so he could have had the shack in goodsprings also, or he might have been originally in the goodsprings shack as a companion but when that was nixed they set him up somewhere else, along with a backstory for the DLC.

So he's basically just like my Courier if he were a remorseless killer who joined the Legion?

Read Ulysses story linked in my sig. Well, I did use creative freedom, to fill in parts of Ulysses' backstory. And it's a colorful one. He was the one who first discovered Hoover Dam as one of Kaisar's frumentarii.

His tribe, the Twisted Hair, were first betrayed and then "absorbed" by the Legion and Ulysses roamed the land as one of Kaisar's best Frumentarius, disguised as a Courier. However, he never really fell under the brainwashing tactics of the Legion. Ulysses was trying to find a piece of the Old World, something to be proud of - somewhere to place his flag. He forgot his own name a long time ago and he took on the name of a mighty General and 18th. US President that he had read about in a pre-war book - Ulysses S. Grant.

You can learn a lot about Ulysses if you find his holotapes in the Big MT and especially during Lonesome Road. You will learn a lot about his motivations. So much has happened to him and his life is filled with sorrow, loss and disappointment. I never kill Ulysses in Lonesome Road, I always fight side by side with him - 2 Couriers against the world!

Also, after training the White Legs in Utah, Ulysses grew totally disillusioned with the Legion and simply left. That's when he moved into Wolfhorn Ranch for a time. It was his hide out, and then he discovered a nation taking its first breath... in the western part of the Divide...

As everyone else said just play all the DLCs. He is mentioned in the first 3 and the climix is the Lonesome Road DLC. Long story short he cancelled after finding out you was still alive after what happened at The Divide(well what is now known as The Divide) and figure the Mojave Wasteland would kill you or if you go to The Divide he will kill you himself along with the NCR and Legion(who he is a ex member of) but only after showing you the kind of destruction you left. He blames you for the death of tribe and no matter how hard he tried to move on he couldn't get over his grief. So he figured the best way get over it was to kill you and destroy the two major factions in the West and East.

Personally I always keep him alive because I always felt sorry for him and I like his character. He is crazy but I like him.

Not exactly. How can I explain my point of view about this char.......

If you are playing with a courier of the Legion, really a lot of people will die, but Caesar is not the Enclave. He did not just want to kill everyone. He have a plan for the future and blah blah blah, we all know here the motivation of this faction.

That is, in the end, yours actions will have a meaning. Something like: "to make an omelet, you need to break a few eggs." An occupational hazard.

But there is something poisonous in Ulysses. Nothing he does, the result is constructive, it is always destructive.

Action: Discover the dam.

Result: a violent war.

Action: train the White Legs.

Result: the destruction of New Canaan and possibly Zion.

Action: forge a aliance with Caesar (not that it was responsible, but it was one of the supporters)

Result: the massacre of twisted hair.

Action: tell Caesar about Divide.

Result: Ceaser send troops to the local, the NCR send the package from Navarro, Booooom.

Action: attract courier to Divide

Result: you can possibly throw a atomic bomb in his former brothers.

And so go on. He's like a protagonist of all fallouts. He walks through the wasteland, their actions shaping the future. But only that everything goes wrong in what he does =p

Even in failure he misses. For example, do not stop the Think Tank.

The guy is unlucky. I like leaving him alive to think about what he believes. The actions of a single man can change a nation.

I like your assesment and insight on this character and his story. But many of the cause-and-effect situations you've described would have happened in some way to any tribal from the other side of the Colorado who got caught up in the Legion's rampage. Ulysses is definitely a damaged man as a result of these experiences, but it is to his credit that he is able to abstract himself from them in a certain way and still act with independant motivation.

Yeah those events would have probably happened anyway, but the point is that he's always the catalyst. It could be any legion courier that could have done it, but every time it just so happened to be him, whether through fate or being very unlucky.
Either way, the point remains that one person can cause all that. If it wasn't him, then it would have been another single person

Yeah, and the guy has the gall to blame the Courier for making a mistake. And why worry about a speck in your friend's eye when you have a log in your own? He was one of my least favorite npcs. I pretend he's high on Jet or something to explain his ramblings.

No, I don't think so. Specific conditions and upbringing and all that shape a person's character. This is my opinion of course, but I think that some people are just kind of gifted or cursed in certain ways. How they adapt to those conditions varies of course. Basically I'm saying that not every common Legion Frumentarii would go to the lengths that Ulysses would, and why he does what he does has everything to do with what he's experienced and what his natural character traits probably are. He displays a lot of individuality and agency in his decisions, and you really see this in the DLC's and in his journals that you find in Lonesome Road.