The Hyl Op colonized their world sometime during the period 2400-2460, apparently as a low-tech utopian society. The original society developed rapidly, but soon became engulfed in a series of bloody civil wars that led to the destruction of the polar ice cap maintenance systems, flooding most of the main cities and causing a major dark age.
During this period the gathering of tools, material and sacred objects from the flooded cities became central both for survival and religion, and the custom of diver princes developed. Rulers had to prove themselves by diving into the city depths and retrieve unique objects (which were placed in temples to the City Gods).
When the Solarian scout probe Opening the Endless Light 5 arrived in the system in 2805 the long isolation was broken, and Solarist missionaries and relief organizations began to help the Hyl Op. Although the political system and religion soon changed to a more traditional Solarist hierarchy, the symbolical diving remained and still continues to this day. The romanticism of the struggling diver princes remains one of the classical myths of the region.