The 'Kenmu' era name, established in the first month of 1334, was the era name chosen in China in the twenty-fifth year of the later Han dynasty, when Liu Xiu (Emperor Guangwu) destroyed Wang Mang and restored the Han dynasty to power; he went against precedent, and despite the fact that it was the fifty-eighth year of the sixty-year cycle and it was taboo to use the character "mu" (samurai) in that year, he overcame the resolute opposition of the nobility and selected 'Kenmu' as the era name anyway.
1334年正月に定められた「建武」の年号は、中国の後漢王朝の25年に劉秀(光武帝)が王莽を滅ぼし漢王朝を復興した際に定めた元号であり、先例に反し、辛酉革命説により「武」の一字が不吉であると断固反対した公家衆の反対を押し切って定めたものであった。