Where does “歴史的仮名遣い” come from?

歴史的仮名遣い (Japanese) comes from Japanese 仮名遣い, from Japanese 仮名, from Japanese 名, from Middle Chinese 名 — name.

歴史的仮名遣い (Japanese): "Historical kana usage", a historically-informed Japanese orthography. Formed in the Edo period by Keichū and taught in schools until 1946, it restores the spellings used in stages of the language (Heian period and earlier) that predate various phonetic mergers

Definitions

"Historical kana usage", a historically-informed Japanese orthography. Formed in the Edo period by Keichū and taught in schools until 1946, it restores the spellings used in stages of the language (Heian period and earlier) that predate various phonetic mergers

Ancestry of “歴史的仮名遣い”, step by step

歴史的仮名遣い traces back through two separate lines of ancestry.

via Japanese 仮名遣い

Step	Language	Word	Meaning
1	Japanese	仮名遣い	kana usage
2	Japanese	仮名	a category of Japanese syllabary scripts: kana; a...
3	Japanese	名	name; reputation; famous, great, noted
4	Middle Chinese	名	name

via Japanese 歴史的

Step	Language	Word	Meaning
1	Japanese	歴史的	historic, historical
2	Japanese	-的	-ile; -ful; -y

Every word from Middle Chinese 名 →Every word from Japanese 名 →Every word from Japanese 仮名 →