He was married to Werna and they had two sons Truls and Rune Gerhardsen and a daughter Torgunn.
Statsministerkuppet: Gerhardsen mot Nygaardsvold: en politisk thriller om maktkampen i mai–junidagene 1945 som skulle endre Norge (2006)
Ole Einar Bjørndalen | Einar Enevoldson | Einar Lönnberg | Einar Örn Benediktsson | Einar Haugen | Einar Gundersen | Bjørn Einar Romøren | Odd Einar Dørum | Einar Gjerstad | Einar Gerhardsen | Einar Axel Malmstrom | Einar Aaron Swan | Rune Gerhardsen | Einar Tørnquist | Einar Thomassen | Einar Schleef | Einar Pettersen | Einar Oscar Schou | Einar Már Guðmundsson | Einar Johansen | Einar Hovdhaugen | Einar Hákonarson | Einar Gausel | Einar Førde |
According to Dagsavisen commentator and former Labour Party politician Arne Strand, Nordahl was one of the three most powerful politicians in the Norwegian labour movement, and thus also in Norwegian 20th-century politics, together with Einar Gerhardsen and Martin Tranmæl.