Especially in Edo, a heavily-populated area, the smallest tatami was used as the standard because in the Mikawa region, when it was ruled by Ieyasu, the smaller tatami, which was called inaka-ma as opposed to kyo-ma, was forced to be used from the standpoint of modesty and frugality.
特に、人口が密集した江戸において、最も小さな畳を基準としたのは、家康時代の三河地方では、質素倹約の立場から、京間に対して田舎間と称して意識的に小さな畳を使用させていた。