Steamwheedle Cartel

The Steamwheedle Cartel is one of the largest and most successful of the Goblin Cartels in Undermine. It is a neutral organization that controls several cities and towns around the world, and has allied themselves with a number of other groups such as the Blackwater Raiders in Booty Bay. The Steamwheedle Cartel has made a great deal of profit from maintaining neutrality in the conflict between the Horde and the Alliance. Their services are always available to the highest bidder, employing anyone regardless of their affiliation if they can produce results.

During the Second War, a Horde ambassador met with a single trade prince and convinced him and his subordinates to join the Horde (while the rest of the goblin race stayed neutral). This may have been Trade Prince Steamwheedle. Some Horde members have tried to improve relations with the Steamwheedle Cartel. Perhaps with enough persuasion, the goblins could be convinced to rejoin the Horde for the first time since the Second War. This is unlikely to happen however, as the trade prince realized his mistake and left the Horde, and the goblin race remembers the mistake and remains neutral to this day.

Towns run by the Steamwheedle Cartel
They also control Smokywood Pastures.

Arenas
The Steamwheedle Cartel also runs the Arena PvP System with the battlemasters all being goblins and the Arena Rewards vendors being located in Gadgetzan, Area 52 aswell as in neutral cities.

Cataclysm
Despite the Bilgewater Cartel - the new playable Goblin race in Cataclysm - joining the Horde, the Steamwheedle Cartel maintained its neutrality.

According to a quick line in the Bilgewater Cartel reputation bar, the Bilgewater cartel now has the title of most powerful cartel on Kezan (though its not known how exactly literally this should be taken).

They have a footbomb team called the Steamwheedle Sharks. They later leave their cartel to join Gallywix.

Playable Goblin Death Knights appear to originally be part of the Steamwheedle Cartel, as evidenced by Gally Lumpstain in A Special Surprise, although they later join the Bilgewater Cartel. They may have just helped Gally join the Steamwheedles, and stayed as Bilgewaters themselves.

Relationship with the Venture Company
The Steamwheedle Cartel runs Ratchet. The Venture Company has also been said to run Ratchet. The Venture Trading Company may be the cartel's parent company. If so, some fans speculate that the Steemwheedle Cartel has some members with internal conflicts of interest. Members of the Cartel sometimes give quests that go against some Venture Company's operations, and also are not as hostile as their parent company. However in the RPG the Venture Co is not as hostile as it is portrayed in the game, and is an independent group that has its hands in almost everything including a sizeable ownership of Ratchet, and Undermine. However, even in the RPG, it also has branches in various locations that are hostile to other groups (or rather other groups are hostile to it), usually in Horde lands

Naming
It was likely named after Trade Prince Steamwheedle (who may be the Goblin Tinker Ratso Steamwheedle, a neutral hero in Warcraft III).

Neutrality
It is interesting that both Trade Baron Silversnap and Marin Noggenfogger, rulers of Bogpaddle and Gadgetzan respectively, make a point to address the neutrality of the Steamwheedle Cartel. It is possible that this reinsurance of their neutrality could be due to the Bilgewater Cartel joining the Horde and that members of the Steamwheddle could be worried that their customers may incorrectly believe that all Goblins work on the same side.

Insane in the Membrane
In patch 3.1.0, a new Feat of Strength has been added. Insane in the Membrane which when with the four Steamwheedle Cartel cities,  with Bloodsail Buccaneers, and  with Ravenholdt and Darkmoon Faire will give the player the title " the Insane".

Go and kill the Southsea Swashbucklers, Southsea Pirates and other related mobs in Tanaris around Lost Rigger Cove (the area to the east of the Caverns of Time). Each mob gives 5.5 rep with Gadgetzan plus 2.5 rep with each of Booty Bay Everlook and Ratchet. (NB: estimated from, sometimes 5 or 6, sometimes 2 or 3, and with the guild perk Mr. Popularity for +10%).