How did the Hutt species gather so much influence, credits and power?

Question

So everyone knows that the Hutts are feared throughout the galaxy for their power and influence. However, few seem to be particularly intelligent or cunning, and tend to rely on their reputation.

This question answers how Jabba is such a powerful crime lord, but it's obvious from legends and even SWTOR that Hutts have been so for many generations prior.

My question is, how did Hutts, large, barely mobile slugs, start to accumulate the wealth and influence that Jabba and the "current" Hutt families now enjoy? Before they had the credits to hire goons to be their muscle, how did they reach the point where they could?

Legends and extended universe are both ok. In universe only, please :)

Answer 1

Well, if you are to go through the Hutts' history on Wookieepedia and follow up on the cited sources, it basically comes down to this:

1. The Hutts rebelled against the Infinite Empire and used the Rakatan technology they seized to forge an Empire.
2. They were, in those early days, a warrior race - note the comments that described they aren't necessarily immobile, especially the younger ones. If nothing else, the Hutt Battle Armor is proof of their ability to make war on their own.
3. The Hutt armies enslaved those species they deemed useful and exterminated the rest, eventually establishing a Hutt empire that was for two centuries the most powerful galactic government in its time. The more worlds they ruled, the more wealth filled their pockets.
4. ~25,000 BBY: The Xim Wars led to Huttese victory over the Tionese Cluster and resulted in the expansion of their territories and the enslavement of more species. More treasure to accrue.
5. ~24,000 BBY: Contact with the Old Republic was made and the Hutts began to raid the systems between the two territories, earning more wealth but also spurring these worlds into seeking Republic protection, leading to a rapid growing in Senate membership.
6. What is known as the Hutt Cataclysm: Basically by 15,000 BBY their mythical homeworld was rendered lifeless. The Hutts believed a celestial apocalypse triggered by a mini-black-hole started it, while scholars believed it was a civil war.
7. Nonetheless, at the end of the Cataclysm the Hutts had to relocate to a new homeworld, and so they explored, discovered the Evocii, and proceeded to scam them of their home planet, taking over and renaming it Nal Hutta.
8. At this point, the Hutts adopted the kajidic philosophy, wherein they abandoned their past warrior ways, delegating the execution of war to their slaves, and fully committed to being what we know them to be today. The Hutt Grand Council was established to keep the various clans in check and prevent a recurrence of civil war.

So you see, from the very beginning after the fall of the Infinite Empire, the use of seized Rakatan technology created most elements of the Hutt civilisation as we know it today: Hutt Space, slavery, immeasurable wealth (with which mercenary armies could be hired and wars waged), a reputation that causes others to either feel immense fear or ambitious greed to become favoured slaves for the similarly immense rewards and delegated power. The Hutt Cataclysm evolved the Hutt identity to its final form as we know it: the migration to Nal Hutta, and the transition from a warrior race into cunning, manipulative masterminds who plan from behind the scenes while their slaves and underlings do the dirty work.

Answer 2

According to EU (The Old Republic materials, I'll need to hunt down specific cite), the basis for Hutt domination was the fact that

• Their planet was part of Rakatan Infinite Empire

• During the fall of Rakatan empire, Hutts gained access to Rakata technology; which was what ensured their power (as per Wookieepedia, most of that early history is not well known and the main source in EU canon is The Essential Atlas).