The Tollan were an advanced civilization encountered by Stargate Command, who possessed massive technological superiority over the Goa'uld. This resulted in a highly stubborn sense of diplomacy, and an global isolationist policy, believing their technological superiority to the rest of the galaxy would sufficiently safeguard their homeworld, Tollana. Having seen their technology misused to catastrophic ends on other worlds, the Tollan refuse to share their advanced technology with any other races. Their reliance on a technological advantage as well as their arrogance impedes their ability to think strategically, as observed by Teal'c. Their superior technology made them overconfident, as they seemed to think their Ion cannons would always protect them against the Goa'uld. However, the Goa'uld always sought ways to find and steal advanced technology, and if they could not simply take it, they would enslave or destroy the more advanced cultures instead. Well aware of the Tollan's powerful technology, the Goa'uld tried to trick and destroy Tollana, but they were unsuccessful until Anubis found a way to make his fleet impervious to the Tollan Ion cannons. With the cannons as their only defense, they met their eventual destruction, which most likely could have been avoided had they taken the threat of the Goa'uld more seriously - and developed alliances and technology accordingly.
The Tollan are peaceful and governed by the Curia, a democratic panel of Tollan officials. Unlike the Nox, they are not pacifist and will destroy any vessel that poses a threat to their planet. However, they aren't outwardly aggressive and are not at war with the Goa'uld, although they apparently have an alliance with the Tok'ra. (SG1: "Pretense", "Between Two Fires")
The Tollan are a secluded race as many in the Curia believe strongly in an isolationist lifestyle. Their highest law states that they cannot share technology with a less advanced race. This law came about when the Tollan, after finding there was another inhabited world, Sarita, in their solar system, gave them a power source to help them. The people of Sarita used the technology to wage war and in doing so destroyed their planet, shifting the orbital path of Tollan. They were forced to evacuate their people to a planet which they named Tollana. (SG1: "Enigma", "Pretense", "Between Two Fires")
A team was sent back to their planet to bury the Stargate, but got incapacitated instead. They were rescued by SG-1, who just arrived on Tollan. They provided medical assistance but because of their lack of interstellar technology, the Tollan called them "primitive". They even rejected help from the even less advanced cultures on another planet, who were willing to offer them sanctuary. The US government, interested in the Tollan technology, planned on interrogating the Tollan, but Dr. Daniel Jackson helped them contact the Nox, who assisted the Tollan in leaving. (SG1: "Enigma")
They are much more advanced than Earth; reverse-engineering an ion cannon, even with the full schematics, proved impossible. They constructed their own Stargate (possibly with help from the Nox as the means to get home, or after they already arrived with their own technology). Tollan technology doesn't include wires, moving parts or anything like Earth's technology. (SG1: "Enigma", "Pretense", "Between Two Fires")
In 2000, two Ha'tak motherships in the service of Heru'ur were pursuing a Death Glider into Tollan space. The automated defense systems shot it down, but the Glider, Skaara, the host of Klorel, who was in the Glider, pleaded to his rescuers for help. The Tollan then began a triad, a type of trial, to determine which sentient mind should keep the body. Jackson and Colonel Jack O'Neill represented Skaara while Zipacna represented Klorel. In a deciding vote, Skaara got to keep his body. However, Zipacna had plans to conquer Tollana, having his Jaffa paint the Tollan ion cannons for destruction, leaving the planet defenseless. SG-1 warned the Tollans that Zipacna was up to something, but their overconfidence caused them to largely brush it off. However, SG-1 approached the Nox Lya for help and convinced her to hide one cannon. When the Goa'uld destroyed the other cannons, Lya uncloaked the cannon so Teal'c could use it to destroy the mothership in orbit. (SG1: "Pretense")
A year later, another mothership approached Tollana but its shields were too strong for the cannons to penetrate. The Curia had no choice but to surrender to the outcast System Lord Anubis, whose emissary Tanith ordered them to construct Phase-shifting weapons to penetrate Stargate Command's iris. One of the Curia, Omoc, who was among those freed by SG-1, opposed this collaboration. The Curia chose to murder Omoc in order to silence him. But SG-1, along with Narim, destroyed the weapons, sealing the fate of the Tollan who were wiped out from orbit. Some Tollan managed to evacuate the planet, but many evacuation ships were shot down and it is unknown how many actually survived the attack. From this moment the Tollan were believed destroyed by the rest of the galaxy, however their civilization survives in the colony of Pellor, remaining hidden from the other peoples. (SG1: "Between Two Fires")
Considering the fact that the name Tollan is the name used to describe two capitals of pre-Columbian mesoamerican empires, specifically Teotihuacan and Tula-Hidalgo, the Tollan may be descended from ancient Central Americans (possibly the Nahua, Otomi or, Totonac) who were brought to Tollan by the Goa'uld around two thousand years ago. Dr. Daniel Jackson speculated that they may have become more advanced than Earth by continuing to advance while Earth fell into the Dark Ages. (SG1: "Enigma")
- The novel Stargate SG-1: City of the Gods establishes the Tollan as one of the human civilizations that were sheltered by the Omeyocan and the crystal skull transport network, making the Tollan descendants of a native Central American society.
Before the dawn of science in Tollan history, they also subscribed to all sorts of supernatural beliefs. One of those beliefs is that when someone is near death, a beautiful female being called the Sher'mau may appear before the dying person to take them to her dwelling in the stars. Captain Samantha Carter thinks the concept is analogous to angels in Earth culture. (SG1: "Enigma")
- Main article: Tollan government
The Tollan were governed by a panel of high-ranking Tollan officials, the Curia. However, this Curia has limited power. For example, it cannot make a contract with the Goa'uld. Many of the members believe strongly in their policy of isolation, sometimes bordering on xenophobia; even trade with other species is out of the question. All sessions of the Curia are, in theory, recorded and available publicly. Concealing such records, or tampering with them, is a crime of such magnitude that murder apparently pales in comparison. High Chancellor Travell is the head of the Curia and apparently the head of the Tollan government. Also, an official protest of Tollan policy is filed with every level of every branch of the government. (SG1: "Between Two Fires")
Less advanced cultures
Tollan technology was very advanced, and superior to that of most other Milky Way civilizations. In the year 2001, Tollan technology was so far ahead of Tau'ri technology that reverse-engineering a Tollan Ion cannon for mass production was well beyond the current level of advancement of the Tau'ri. However, after the Tau'ri gained the superior knowledge and technology of both the Asgard and the Ancients, their technology level has leaped far beyond that of the Tollan.
One of the most impressive examples of Tollan technology is the Ion cannon. These powerful weapons are capable of destroying a Goa'uld Ha'tak with even a single shot and have served in Tollana's defense several times. The Tollan have also constructed their own Stargate with the help of the Nox, since their new homeworld did not originally possess one. The most important Tollan buildings were protected by technology that disabled all weapons it detected (including Tau'ri projectile weapons and Goa'uld Staff weapons) while leaving the hand weapons carried by their own security forces unaffected. They also developed emotion-recording technology and phase-shifting devices that allowed the user to walk through solid matter, including Earth's iris. Also, every Tollan had a small implant in his/her body that monitored the carrier's health. In case of a medical emergency, this implant would automatically alert the emergency services. This small device could also be used to track one's position, although this was highly illegal.
Tollan technology contains no wires, moving parts, circuitry, or anything else found in normal mechanical devices, decreasing the possibility of compatibility with technology from other cultures. Most of it is constructed from an alloy composed of Trinium and various other elements. (SG1: "Enigma", "Pretense", "Between Two Fires")