It should be noted that although Kei HARA was known as a commoner Prime Minister, he was in a family line of the chief vassal of the domain of Morioka and thus disliked the new nobility represented by Yamagata; this led him to continually decline the peerage.
ちなみに原敬は平民宰相として知られるが、盛岡藩の家老の系譜であり、山縣に代表される新華族への嫌悪感もあって、爵位の授与を回避し続けた人物である。