Almost all mainstream large language models are secretly obsessed with Japan.

Especially when it comes to food, art, social life, and entertainment, Japan is almost always the first thing the models think of.
Researchers tested eight mainstream models including GPT, Claude, DeepSeek, and Gemini.
They posed more than 30k cultural questions with no specified location in 24 languages, covering food, art, and family life, and then let the AI choose a country to answer.
The results showed that regardless of which language was used, Japan appeared frequently.
Even more interestingly, this bias mainly emerged after supervised fine-tuning. Before fine-tuning, the base models would choose different countries, but after being trained to answer more effectively, the answers began to rapidly concentrate on Japan.
The reason may be that Japanese culture is too recognizable in the training materials—sushi, anime, tea ceremonies, cherry blossoms—each one can instantly map to a specific answer.
At the same time, Japan is often portrayed as a country where tradition and modernity coexist, with a distinct culture. When models need to quickly pick an example, Japan is often the safest and easiest choice.
Over time, Japan has been固ified into the default template for AI answering cultural questions.