The oldest existing oraimono, "Meigo Orai" (Meigo's Correspondence), is believed to have been written by FUJIWARA no Akihira, a scholar in the late Heian period who served as Monjo hakase (professor of literature) and Daigaku no kami (Director of the Bureau of Education) (This book is also called "Unshu Orai" or "Unshu Shosoku" and is comprised of 12 months' worth of example sentences which are related to events of the respective months).
現存する最古のものは、文章博士や大学頭を務めた平安時代末期の学者・藤原明衡のものとされる『明衡往来』（『雲州往来』・『雲州消息』とも）と言われており、月ごとにその月にまつわる行事などの文例をまとめた12ヶ月分によって構成されている。