SINNOH
The snow-covered northern point
Beyond all else, there is Sinnoh. The region goes farther north than every other, only to be matched by the Galarian Crown tundra. But to only look at Sinnoh's status as the northernmost region would be ignorant - it's also a region of rich myth and legend, and is said to be the first region created by Arceus themselves.
GEOGRAPHY
Sinnoh is, to its core, a mountainous region. A massive mountain range runs through the middle of the region, separating two halves. It's not all just sheer cliffs, though. Sinnoh is also home to dense and vast cold-weather forests, tundras, and in the southernmost end of the region, warmer areas near the sea. Only the true northern areas of the region get snow all year, otherwise, the rest of the region is fairly temperate.
HISTORY
Sinnoh's history is, for the most part, shrouded in a thick layer of mystery. It has one of the highest levels of divine activity (next to Hoenn), which tends to make reading the region's history difficult for historians. Still, that means that Sinnoh has some of the most solid myths of any other region, and they continue to inspire the region's people and pokemon to this day.
POPULATION
Due to the region itself being cut off by a massive mountain range, Sinnoh actually has a smaller population relative to its size. Many of Sinnoh's residents have been there for years, though the region is warm and welcoming to outsiders. Pokemon wise, it's much of the same case - Sinnoh's dex is on the smaller side, due to the region's general remoteness and climate. It's home to many pokemon that are able to tough out the cold.