- 1951
- Mr. Takayoshi Ezoe (Current Foundation Chairman) begins teaching Japanese to Catholic missionaries at the St. Joseph Institute of Japanese Studies. This becomes the foundation of the CLC Culture and Language Center Japanese Language School.
- 1953
- The late Ms. Setsuko Ezoe (Vice-Principal) begins teaching at the St. Joseph Institute of Japanese Studies.
- 1975
- The Shinjuku Japanese Language Institute was established In collaboration with Mr. Takahide Ezoe in West Shinjuku, Tokyo, with the objective of teaching Japanese to international students. CLC is designated as a culture center.
- 1976
- Mr. and Ms. Takayoshi Ezoe begin teaching Japanese in Singapore.
- 1978-83
- Mr. Ezoe is appointed by the Japan International Exchange Fund to manage the Japanese Center in Singapore.
- 1982
- SNG expands and moves to Takadanobaba.
- 1983-86
- Mr. Takayoshi Ezoe is appointed by the Japan International Exchange Fund as Consul General in charge of Japanese Language Instruction in Hong Kong.
- 1985
- SNG receives official recognition from the mayor of Tokyo. SNG is separated into two schools, SNG & CLC.
- 1988~90
- Mr. Takayoshi Ezoe is appointed by the Japan International Cooperation Association (JICA) as Director of Japanese Language Instruction in San Paolo, Brazil.
- 1989
- SNG’s current main building is erected. SNG and CLC are recognized by the Association for the Promotion of Japanese Language Education (Nishinkyo).
- 1990~93
- Mr. Takahide Ezoe is appointed by the JICA as Director of Japanese Language Instruction in San Paolo, Brazil.
- 1999
- SNG is approved by the Ministry of Education as a college prep school. SNG and CLC are approved by the Tokyo Metropolitan Government as an educational foundation, forming the Ezoe Education Foundation. CLC moves to its current building.
- 2000
- SNG celebrates its 25th anniversary. CLC is approved by the Ministry of Education as a college prep school.
- 2003
- SNG and CLC merge, forming the current Shinjuku Japanese Language Institute.
- 2005
- SNG celebrates its 30th anniversary.
- 2015
- SNG celebrates its 40th anniversary.
- 2016
- Research building construction completed.
- 2019
- Consignement by the Tokyo Metropolitan Government Office for business Japanese
- 2020
- Start of Fully Online Classes