The first persons recorded as Tairo in the history were Toshikatsu DOI and Tadakatsu SAKAI (the lord of Obama Domain in Wakasa Province) who were promoted to the post in 1638 by Iemitsu TOKUGAWA.
記録で明らかところでは、1638年に徳川家光が土井利勝・酒井忠勝(若狭国小浜藩主)を大老に格上げしたのが始まりとされる。