Aldean

Rashella, an Aldean female. Image by Paramount.

The Aldeans were a civilization native to Aldea, which was considered only a legend for thousands of years.

The society was self-contained and self-sustaining with incredible technical sophistication providing daily needs. Similar to cultural myths of Neinman on Xerxes VII or the Earth story of Atlantis, Aldea was said to have shed its past of violence and cultural conflict and evolved to a pure state, devoting themselves to culture and art. The Aldean culture developed by emphasizing the fundamental principle that for "everything taken, something must be returned." It was this principle that allowed their civilization to ascend to incredible heights in technology and art.

Having reached enlightenment, hundreds of centuries ago, the Aldean society retreated from the rest of the Milky Way Galaxy. To facilitate this, their Progenitors built an enormous and advanced planet-wide defense system. The system, run by the computer called the Custodian, maintained an immense cloaking device and defense shield, in addition to a repulsor beam] powerful enough to push starships several hundred light years away.

However, the long-term effects of the planet's defenses were extremely damaging. Millennia after the Aldeans retreated behind their cloak, cumulative wide-spread environmental damage, including depletion of their ozone layer, began to take their toll. The Aldeans suffered from long-term chromosomal damage from radiation poisoning due to exposure to their sun's ultraviolet rays. By 2364, the entire population of Aldea was infertile and depleted. No child had been born on Aldea for more than thirty years, and most of native wildlife on the planet, including all the fish in their oceans, had long ago become extinct.

To try to rectify their dire situation, they attempted to kidnap various USS Enterprise-D children in the year 2364, including Wesley Crusher, to repopulate their planet. After the failed attempt, the Aldeans agreed to accept help from the Enterprise to relearn how to properly use their technology, never again to use their shield or cloaking device, and medical treatment reversed the radiation poisoning in the population, which would restore fertility in time.

On that day in 2364, when the Enterprise deactivated the Custodian for them, the sky ceased to be purple, and took and the natural gold and and orange colours of its atmosphere. As beautiful as the planet became, it was also bared to the threats of the Galaxy. More so, since Starfleet could do little in terms of helping the Aldeans decipher and learn how to use the Custodian.

Physiology

The Aldeans were physiologically very similar to Humans, which presumably was a deciding factor when they contacted the USS Enterprise-D in 2364.

Culture & Customs

Aldean society was structured into unis, or social groups, which specialized in a particular art or pursuit such as medicine or science. Within each group students were fully devoted to their discipline. The Aldeans had perfected their system of education and study to the point where the natural abilities of the individual blossomed very quickly, sometimes within hours or days of the student's first exposure to a medium.

The Aldeans were split into several factions after the events. One faction, lead by Radue, favored joining the Federation. Another faction wanted to ally with the Romulans. A third with the Klingons. Yet another faction wanted Aldea to remain isolated. In the end, it was the Klingons Empire who became the faction that the Aldeans allied themselves with. Because of it, some fledgling signs of Klingon culture had become to influence the Aldeans as of the year 2381.

Source: Memory Alpha