Meaning & History
Moriyama (森山) is a Japanese surname composed of two elements: mori meaning "forest" and yama meaning "mountain, hill" — literally "forest mountain." This pair of richly visual natural meanings is typical of Japanese surnames, many of which derive from landscape features found near the ancestral homes of the families that first bore them. The surname has a pleasant natural imagery that speaks to family lineage deeply rooted perhaps in actual toponyms along the mountainous, wooded regions of Japan.
While Moriyama is a relatively common surname in western Japan, it also finds a counterpart as a Japanese surname in the city in Shiga Prefecture called Moriyama. According to recent estimates from late summer 2021, Moriyama in Shiga Prefecture had a population of roughly 85,485 residents living in just over 34,300 households. The name bears specific meanings associated partly with that overall character of the place. Geographically, the city residents are at the place where the Yasu River flows from the Suzuka Mountains and passes into Lake Biwa as an alluvial fan. Moriyama is on flat land near Lake Biwa. The characteristic flatland, yet adjacent green, raised areas—mountains and forests—continues an ideal landscape to showcase mori of forest and yama of mountain. Moriyama the city collects rains and occasionally floods from the waters in Lake Biwa's waves along the coastal north seas of numerous Japanese urban centers altogether known among similar tectonic dynamics for more many in the Kansai region. The old village, historic earlier gave surname origin. The locale likely gave its common suffix to most people using the custom established by Meiji, the typical overall late-19th century spread from localized clans acquiring the name toponym too.
Related Japanese surnames with parallel compound from “forest” (mori) culminate multiple forms—including Morimoto (“forest origin/base”) or Moriya that keep the two-element nature exact mix of habitat and altitude effectively doubling names as being entire typical custom over Korea formerly as near roots system practice—while some direct variations exactly covering final same native derived.
Sources: Wikipedia — Moriyama, Shiga