Meiji Shrine

Before the creation of Meiji Jingu, the area was known as the South Toshima Imperial Land, a royal property, which consisted mainly of fields and a landscape resembling wasteland, except for the current area of the Gyoen. Scholars of the highest caliber were gathered to plan the construction of the "Eternal Forest," dedicated to Emperor Meiji and Empress Shoken, where people could quietly pray. Most of the trees planted were donations, with about 100,000 trees contributed from across the country. A total of 110,000 young people participated in labor service for the construction work, sweating through tree planting and the creation of pathways in this forest of Meiji Jingu.

In the construction process, forestry experts such as Seiroku Honda, Taketoku Hongo, and Keiji Uehara considered what types of trees to plant to create the "Eternal Forest," concluding that evergreen broadleaf trees, such as Chinquapin, Oak, and Camphor, should be the primary species to be planted in anticipation of the future. The reasoning behind this decision was that by the Taisho era, pollution had already progressed in Tokyo, and many large and old trees in the city were dying one after another. Thus, they concluded that only evergreen broadleaf trees could thrive in Meiji Jingu a hundred years ahead.

However, then-Prime Minister, Shigenobu Okuma, insisted on having the forest resemble that of the Ise Shrine or Nikko Toshogu, stating, "Are we going to turn the Jingu forest into a thicket? A thicket is undesirable; it should be a cedar forest." The forest committee strongly opposed Okuma's opinion, explaining from a forestry standpoint that while cedars grow best in humid valleys, this area of Yoyogi was unsuitable for them, and cedars would not thrive in an urban environment.

In April 1945, many of the shrine’s buildings were destroyed in an air raid, but the forest served as a refuge for people and suffered little damage. It may have escaped significant fire damage because it was composed of broadleaf trees rather than easily flammable conifers.

As part of the 50th-anniversary project of the shrine's enshrinement, a comprehensive survey of the grounds centered on tree assessment was conducted, the results of which were published in 1980. A second comprehensive survey, which included an investigation of biodiversity involving animals, was conducted for the 100th anniversary of the shrine, with its report published in 2013. These studies academically investigate how the forest has developed.

At the start of the construction, the inner garden contained approximately 120,000 trees of about 365 species, including native species. According to the second comprehensive survey, this number has decreased to about 36,000 trees of 234 species. Natural selection has taken place, and the trees have grown larger. Furthermore, around 3,000 species of living organisms, including new species and endangered species as well as rare plants and animals in Tokyo, have been reported, generating considerable interest.