19,000 years prior to the Battle of Yavin (BBY), the Galactic Republic was experiencing its Great Manifest Period. This era, which had its genesis 1,000 years prior, was defined by a swift outward movement from the Core Worlds, extending into the regions of Wild Space situated to the east of the galactic center. Separately, on the isolated world of Kamino, located outside of the galactic plane, a significant alteration in the climate was unfolding. The ice covering its surface began to thaw, resulting in widespread flooding that compelled the native sentient species to move their cities.
Before 19,000 BBY, the planet of Kamino, situated outside the galactic disc, was a terrestrial world characterized by relatively small oceans. These confined bodies of water were densely populated with eels and cetaceans, leading to overcrowding. On the land, the Kaminoan species, known for their tall and slender physique, had evolved in the small marshes and lowlands. These natives established cities along the coasts of these oceans, with Derem being one example of such a community.
Around 19,000 BBY, Kamino underwent a dramatic change in its climate. The glacial ice, previously limited to the planetary ice caps, started to melt. The melting ice caused the low-lying marshes where the Kaminoans originated, along with the small oceans, to flood, submerging the existing landmass. Simultaneously, within the Galactic Republic, the Great Manifest Period continued its course. The Republic persisted in expanding and settling territories to the east of the Core Worlds, venturing into what would eventually be known as "the Slice."
Within a couple of centuries, the entirety of Kamino's surface land was submerged beneath water, reaching depths of hundreds of meters in certain areas. The former urban centers, including Derem, and architectural landmarks, such as the Clock Spires of Harai Nova, were completely underwater. To ensure their survival, the Kaminoans adapted their existing technology to construct their cities on elevated stilts above the rising water. Furthermore, the Kaminoans employed genetic engineering as a means to conserve numerous species that perished due to the inundation. In the wider Galactic Republic, the Great Manifest Period's expansion persisted for an additional 2,000 years, until the rival Core Worlds initiated a series of wars to gain dominance.
The sole mention of the year 19,000 BBY is found within The Essential Atlas, which was released in 2009. While the Great Manifest Period is detailed in other sources, such as The New Essential Chronology, the specific year of 19,000 BBY is not explicitly referenced. In the Atlas, this year is specifically cited in the context of the planet Kamino, where the details surrounding the planet's climate transformation are recorded. Elsewhere in the Atlas, the year is indirectly referenced when discussing the Great Manifest Period.