Bokusan Nishiari (Japanese: ????; romaji: Nishiari Bokusan), was a prominent Japanese Soto Zen Buddhist monk during the Meiji Era.
He is considered one of the most influential Soto priests of the modern era due to his elevation of the status of the school's founder Eihei Dogen, the many prominent positions he held during his lifetime, and his almost equally prolific disciples Sotan Oka and Ian Kishizawa.
Nishiari's positions included abbot of Soto's head temple Soji-ji, professor at what would become Komazawa University, and chief priest, or kancho, of the entire Soto school.
His student Sotan Oka was the first abbot of Antai-ji and a teacher to both Kodo Sawaki and Hashimoto Eko, each of whom are the source of Zen lineages in the United States.
His student Ian Kishizawa taught Shunryu Suzuki, the founder of the San Francisco Zen Center.
Though critical of Nishiari later in his life, the founder of the Sanbo Kyodan sect Hakuun Yasutani also studied extensively with him and Kishizawa.
The Buddhist studies scholar William Bodiford writes of Nishiari: Today, when someone remembers Dogen or thinks of Soto Zen, most often that person automatically thinks of Dogen's Shobogenzo.
This kind of automatic association of Dogen with this work is very much a modern development.
By the end of the fifteenth century most of Dogen's writings had been hidden from view in temple vaults where they became secret treasures ...
In earlier generations only one Zen teacher, Nishiari Bokusan (1821–1910), is known to have ever lectured on how the Shobogenzo should be read and understood.