The Mintakans were a proto-Vulcan humanoid species native to Mintaka III who existed in a Bronze Age state of technology. Once the Mintakans were religious and superstitious and believed in notions such as spirits of the dead haunting the living, supernatural beings, or that the stars controlled their fate.
From millennia before 2366, despite their relatively minimal technological advancement, Mintakan culture had been evolving to become highly empirical, having had long since rejected the aforementioned superstitions, as well as collecting astronomical and archaeological data for several generations. It had also become a tradition that Mintakan women always walked in front of the men as a sign of ownership, and to stake out a negotiating position for any services which might be asked of the man.
In 2366, a Federation anthropological field team studying the Mintakans accidentally exposed the primitive culture to 24th century technology when the duck blind from which they were operating had a reactor failure. The USS Enterprise-D responded to the situation and unknowingly worsened the cultural contamination when the Mintakans observed their comings and goings. As a result, the previously discarded beliefs in supernatural beings began to resurface in the village most directly affected. This would eventually lead to their mistaking Jean-Luc Picard for the Overseer, one of their gods. To mitigate the contamination of their culture resulting from the unintentional and accidental violations of the Prime Directive, Captain Picard abducted the local leader, Nuria, in order to give her a guided tour of the ship to explain that the beings they discovered are simply mortals with advanced technology.
Unexpectedly, Nuria believed that this proved that Picard was indeed the Overseer. It took her seeing the death of one of the anthropological team to prove to her that Picard and his people were mortal. When they returned to the planet, Liko finally believed the truth when he almost killed Picard with a bow and arrow.
While cultural contamination occurred, it was relatively limited. The local Mintakans gained only the knowledge that sentient life inhabited many worlds besides their own and that many seemingly impossible or divine feats, such as instantaneous transport and interstellar travel, could be achieved with a sufficiently high understanding of technology. This knowledge may or may not have spread to the rest of the planet; possibly the tale would have been too fantastic to be believed. The Mintakans were left to continue on something close to their original path of cultural evolution, as the Enterprise crew refused to allow access to advanced technology, explaining that the Prime Directive proscribed additional contact or interference from the Federation and Starfleet until the Mintakans reached a sufficient level of independent development in the far future (meaning a warp-capable culture, of course). Judging by Nuria's willingness to learn about the possibilities and limitations of a more technologically advanced life, Captain Picard was firmly confident that the Mintakans would be able to achieve the same on their own. (TNG: "Who Watches The Watchers")
Knowledge of the Mintakan incident remained restricted and highly unlikely to be possessed by a Starfleet cadet. Later in 2366, "Cadet Mitena Haro's" knowledge of the Enterprise's visit to Mintaka III led Captain Picard to realize she might be an impostor. (TNG: "Allegiance")
According to the script, the "Mintakans look very similar to Vulcans -- they have the same pointed ears and arched eyebrows. Note: Though Mintakans are a cool-headed, rational people, they are not as stoic and emotionless as Vulcans."