Christiansen became the first British athlete to claim triple gold in London by winning the Grade Ia freestyle test at Greenwich Park.
That followed silver medals for Sophie Wells and Deb Criddle in their freestyle tests as Christiansen lifted Britain to 11 medals, including five golds, in the equestrian events in London.
With two riders fewer than in Beijing performance director Will Connell was understandably delighted with the achievement.
He said: “At Beijing, we won 10 medals with seven riders. Here we’ve won 11 medals with five riders and exceeded our target. This is the first time anyone has won medals in all five grades in the individual and freestyle.”
Christiansen made it a full house on her horse Janeiro 6 with a Paralympic record of 84.75.
“I was always going to enjoy that. Sometimes I can get a bit carried away, but I relaxed and gave it everything I could,” said Christiansen who produced a daring routine on her way to victory.
“Knowing my friends and family were in the audience was really special. Some of them had never seen me on a horse, let alone win a medal.
“I know the composer Owen Gurry really well and he knows my test. It’s a bit groundbreaking as I’ve got a bit of Shakespeare as well as the Big Ben bells.”
Criddle’s performed her freestyle routine on LJT Akilles to the Beach Boys’ Good Vibrations, earning 78.55 and second place for the second time at the Games.
She said: “My freestyle was truly freestyle. I had a slight momentary hesitation, which meant that I went into a movement I shouldn’t have done at the time.
“I ad-libbed and picked it up from there. That’s where I did well, because I did not let it throw me. He was really with me. My medium trot had a little loss of rhythm, which would have been a little bit costly, but other than that I am over the moon with how he was.”
For team manager David Hunter, the support of 11,000 fans was a major factor in his team’s success.
“The atmosphere here has been a huge bonus,” he said. “There has been great feeling. The spectators have been so caring, some knowledgeable, some not, but so enthused. It is the biggest audience any para-equestrian competitor of any nation has ever ridden in front of.”