How did the Kroots get into the expanse? Could this be a good excuse to get a group of Astartes lost in the expanse and entering service of an RT?

Usually, in my games there is a warp gate somewhere in the Koronus Expanse, possibly now closed by a warp storm or else only one-way.

(so you don't see Tau coming in or Iron Hands/Ultramarines/Scythes coming and going regularly)

It's explained in the Deathwatch RPG. In the Koronus Passage between the Screaming Vortex and the Void Dancer's Roll, there is an ancient warp gate (possibly of Eldar Origin) that serves as passage between the Maw and the Jericho Reach. It's been kept secret (and Space Marines still secretly use it), but it's apparent the gate works both ways, (hence the kroot).

Now the gate is fortified by the Deathwatch and the Imperial Guard (on the Jericho Reach Side), but in ages past the Kroot could have moved through the gate to the Koronus Expanse, which is why the beaked xenos now thrive in the Expanse.

It's also explained in RT: BFK (Rogue Trader: Battle Fleet Kronus) as Zone 15 and Fleet Base Metis (pg 61). A place that is blocked off by Imperial Warships and the penalty is death for any who enter who are not authorized. It also has a Ramilies-class Star Fort nearby the gate.

You think a grand endeavor for the Imperial Navy could get a Rogue Trader access to Jericho's Reach?

Yes. And it even states that some RT's have access to the gate and are allowed to enter and exit as they please (as long as the RT's visits are announced and they don't share the secrets of it's location, origin, and where it leads to). I would think any RT group that is trustworthy with the Imperial Navy and it's Administration would sooner or later be offered to dock at Fleet Base Metis and learn of this secret.

Calixis Sector bears the brunt of running and supplying the Achilus Crusade happening behind that warpgate right now. It should be quite easy for an enterprising Rogue Trader to get in on the action.

Calixis Sector bears the brunt of running and supplying the Achilus Crusade happening behind that warpgate right now. It should be quite easy for an enterprising Rogue Trader to get in on the action.

That is true, but other than fighting a bunch of aliens, what do the Rogue Traders get out of it? As you pointed out in another topic:

-Leaders of the Achillus Crusade regularly petition you to support their cause, but you politely decline them because "Tyranids aren't lootable".

I could think one group paying handsomely if you can procure live speciment.

Beast Houses

How did the Kroots get into the expanse? Could this be a good excuse to get a group of Astartes lost in the expanse and entering service of an RT?

Also note that the Kroot are more widespread than the Tau Empire. The Kroot have a basic capability for Warp Travel (unlike the Tau) thanks to inherited Ork genome, and mercenary kindreds pop up across the galaxy (without tau approval or knowledge)

Calixis Sector bears the brunt of running and supplying the Achilus Crusade happening behind that warpgate right now. It should be quite easy for an enterprising Rogue Trader to get in on the action.

That is true, but other than fighting a bunch of aliens, what do the Rogue Traders get out of it? As you pointed out in another topic:

-Leaders of the Achillus Crusade regularly petition you to support their cause, but you politely decline them because "Tyranids aren't lootable".

To be fair, just because you can't loot them doesn't mean you won't get paid. It just means you won't get paid twice. (Or, well, you could probably convince the Navy to pay you to enter the war, and then individual planets to pay you to rescue them, so you could still get paid twice, just not three times)

I've often considered a RT game in Jericho. So long as the group is more combat-ready, they could do a lot, help some important folks, and benefit. There are many worlds there, like in the Koronus Expanse, that have been without Human rule for millennia, and the rewards and prizes there could be vast. Of course, the threats there are more serious, with several active wars going on (hence the increased combat-readiness) but if you can fend off a few Necrons, and Nids, you should be good against everything else. Just be careful who you piss off, as the leaders there are more attentive, and might not like you making chummy with the Tau, or sporting Necron upgrades to your ship. Also, "someday" it might be Imperial territory, again, and then your right to be awesome there goes poof.

As an off point, I thus wonder if the Astrarium of the Processional would contain the JM warpgate's location, thus giving the players a starting point to want to go through?

.As an off point, I thus wonder if the Astrarium of the Processional would contain the JM warpgate's location, thus giving the players a starting point to want to go through?

Sounds like a great plothook!

I remember reading Rogue Traders usually start of with some mission when they first acquire a Warrant of Trade. You could start with a newely formed dynasty who have been tasked with achieving a number of military objectives in Jericho Reach in return for their warrant. This means not only do the Imperial Navy allow them to use the gate but in fact strongly 'encourage' them to use it.

There would be a lot of loot to be made in such a military hotpot even if the risks may be greater and also plenty of other enemies to face (and loot) other than tyranids. In fact some enterprising young Rogue Traders may even find it profitable selling arms to both sides of the conflict. There are also plenty other clandestine methods of acquiring wealth under the fog of war.

On many levels, I often see the setting of Deathwatch as ideal for a game of Rogue Trader. In most ways, there is really nothing that the Expanse possesses that the Reach is lacking. There are numerous worlds, long lost to the Imperium, possibly rife with STC devices, lost archeotech, alien treasures, or what have you (if the Nids haven't eaten them), Chaos to fight, Orks to fight, and such. In addition, there are close-by Imperial assets, both to benefit you, and maybe to actually give the GM a little rein way to keep his crazy players in check. Easy access to Imperial Guard and Navy, if you want to help them do stuff, whether it be move a specialist team, haul supplies, or what have you, and you could do some of the same for the Astartes, which the Expanse is mostly (supposed to be) lacking. Active war makes for more active contracts, and more nice chances to fire on enemy craft. You need to plan for more combat, more likely, and some of the foes are more clever or daring, but it could work. Also, with few or no active Rogue Traders in the area, it's a juicy market. I've never really seen a downside to the idea, barring that maybe access to the warp gate would be limited, so getting back to the Imperium, as a whole, could be tough. Still, it could be an awesome way to do things. Aside from that fool Ebongrave, I also don't imagine too many people there resisting the idea of another loyalist ship, adding its firepower to the pile, to help win the war. I like to think that a small part of Only War's story is that the Segmentum Command is intentionally not winning the Spinward Front war because its outcome is, to some extent, less critical, and they are using it as a cover to the Jericho Crusade. There are less troops in either forum, but the masquerade is important. Winning in the Reach, however, IS important, with the possibility of Chaos, Nids, or Necrons flying through that gate, and wrecking the Expanse and Calixis, practically without a fight. Thus, your aide could garner much reward. If you are a less ideal Rouge Trader, YOU can still benefit greatly, even of the Imperium's forces don't.

That's definitely right Venkelos.

Also remember that Rogue Traders can be found anywhere and will usually have bases of operations set up in Imperial Space in order to supply and support their operations in unkown space.

The Koronus Expanse is simply the setting for the game because they have to set it somewhere and of course unexplored and unclaimed space is most suitable for the game. You can set up an adventure anywhere you like.