The Whangapoua man, who had been living in Vanuatu for about 10 years, died in hospital soon after. His family were then given the tragic news.
"My heart just broke," Mr Christian's granddaughter Amylee Kitto said.
"As far as I'm aware, he was trying to stop a fight. A man was beating up his wife. Granddad jumped in to try and stop it and he got beaten to death.
"It's him through and through - he'd always put himself last and everyone else first.
"If he ever saw someone in trouble, he was in there without a thought for himself. He put everyone first whether he knew them or not."
Ms Kitto had heard that other people witnessed the man assaulting his partner, but did not intervene. It upset her that he was the one who took the risk if others just watched.
"That's why it's ever more heartbreaking that he passed in this manner. It just makes it even worse. I'm proud, but that little selfish part of myself wishes he didn't help."
Ms Kitto spent a year living with Mr Christian on his yacht in Vanuatu.
She met him for the first time when she was 18. Her mother, Mr Christian's daughter, was adopted out and when Ms Kitto turned 18 she decided to find him.
"I thought I'd like to get to know my family. I tracked him down in Vanuatu and rang him.
"I said 'hi, I'm your granddaughter and I've never met you, but can I organise to come and visit'."
"He told me to get on the next flight, so I went over for 10 days. The second I got off the plane he was right there with a big smile and a big hug."
Ms Kitto and Mr Christian formed a close relationship and she broke down in tears speaking about him yesterday.
"He was one of those people who fully accepted everyone for completely who they are.
There was nothing bad about him. Every person was a chance for a new friend, he was wonderful.
"He was a typical Kiwi guy, he could play anything on the guitar and he cooked a mean feed.
"He would sometimes put a hangi down and the food was always amazing, and he brewed his own beer."
Ms Kitto said her grandfather was a real character, and was well known and liked by the Port Vila locals.
Since moving to Vanuatu Mr Christian had worked on several boats, taking tourists for cruises and more recently as skipper of the 33m catamaran Big Sista between Port Vila and Luganville Santo.
Ms Kitto said he loved the water, and his life in Vanuatu.
"His whole life has been spent on the ocean. Being able to live on his yacht in Vanuatu was just paradise for him."
She said Mr Christian always had a smile on his face, and she felt lucky to have the chance to get to know him.
"If I end up even half the person he was, I'll be happy.
"He just loved people, he was such a friendly and genuine guy. This is such a tragedy."
Vanuatu Police last night said a local man had been charged with intentional assault causing death.
Police Chief Inspector George Twomey said the man, 30, appeared in court yesterday. He was remanded in custody for two weeks, while the investigation was completed.