How are wine regions defined?

These are not boundaries we invented

We do not draw a line around a place simply because it feels like a wine region. The table includes divisions actually used by national, prefectural, municipal, or regional-bureau bodies as wine regions. We adopt a region only when its name and covered area can be verified in a prefectural plan, municipal description, or regional government material.

Nagano’s wine valleys, Katsunuma as described by Koshu City, Yoichi-Niki as introduced by Yoichi Town, and Sorachi as handled by the Sorachi General Subprefectural Bureau show how the body and the scope can differ. We do not combine nearby municipalities or similar landscapes ourselves and create a new regional name.

Keep GIs separate from sub-prefectural regions

The National Tax Agency’s geographical indication system allows qualifying alcoholic beverages to use a correct place name under defined production standards. A GI such as Yamanashi or Hokkaido can cover the prefecture as a whole; it is not a division below the prefectural level. We therefore do not place a prefecture-wide GI in the same regional layer as a sub-prefectural division such as Katsunuma or Yoichi-Niki.

This separation is not a judgement about the value of a GI. It keeps a legally defined geographical scope distinct from a regional name used by a municipality or bureau. Readers can then see which system or public document each place name comes from.

The “source of the definition” column points to the public body that defines or introduces the region, not to the source for an individual winery. It is there to verify the municipalities, scope, and usage of the name. It does not mean that every producer listed in that area uses the regional name.

What an unassigned producer means

Many producers do not have a region assigned in the table. That does not mean they have no region. It means that we could not match their location to a public division that this site can adopt and verify. We do not fill regions by intuition where no official division has yet been confirmed.

Our reading: Region names are used for different purposes, including public policy, local development, and tourism. That is why it matters to keep the question “who uses this division?” as a source, rather than flattening every place name into one fact. A blank is not a gap in geography; it marks the boundary of what has been verified.