The honours list also recognises many other well-known New Zealanders, including All Black World Cup coaches Steve Hansen and Wayne Smith and Academy Award winner Bret McKenzie.
"This can go up next to the Oscar, which is currently next to the nappy cream on top of the piano," McKenzie said.
Sir John Kirwan's wife, Fiorella, knew little of the implications but when he explained the title was largely for his work in mental health, the family understood.
After his battles with depression, Sir John became a spokesman and campaigner in New Zealand for mental health issues. He made his problems public to encourage other people to seek help.
"I remember the day they asked me to do the awareness campaign. It was the hardest thing I ever considered," Sir John said.
"My philosophy all the way through about mental health is that if I can help one person, it will be great.
"If you ask me what is depression, it is the best and worst thing to ever happen to me. But my whole journey has been positive.
"There were scary times because of the stigma attached to depression, but I have tried to break those down because it is an illness, not a weakness."
When he was asked to accept the knighthood, Sir John requested 24 hours to think about it. He wondered what people would think and whether it was appropriate.
In the end, the 63-test All Black accepted it for his work outside his sporting sphere.
"It seems like all this is a long way from Mangere," said Sir John of his upbringing, his time at De La Salle College and his butcher's apprentice beginning.
"Mum's still alive and Dad would also have been really proud, though I can just imagine him telling me something like, 'Don't get too big-headed, boy.'
"I've accepted the award on behalf of all those people who are suffering, to show there is hope. My main message is that there is always hope, there is always help, there is always a way out of the troubles."
Sir John has lived in Europe for the past 10 years, and has coached Italy and Japan.
He coached the Barbarians in three tests against England, Ireland, and then Wales yesterday in Cardiff, and is looking for his next appointment.
His target is the Blues, in Auckland.
He has spoken several times to the Herald about his interest in coaching a Super 15 team as a pathway to his ultimate target of making the All Black panel.
He said he would apply this week for the Blues job, which is being advertised after incumbent Pat Lam's lack of success.
