Thirty-five new citizens, from countries including Nigeria, Britain, Canada, the United States, Malaysia, South Africa, Ethiopia, Germany, Korea, Taiwan and Pakistan, were sworn in at the ceremony.
Mr Cull said the presentation was a "special and significant ceremony".
"While our Maori heritage goes back over 1000 years, New Zealand is still a young country with a diverse mixture of cultures and people," he said.
Among the new citizens was Dunedin City councillor Lee Vandervis' wife, Antonie, who was born in Murnau am Staffelsee, Germany.
Dunedin mayoral candidate Olivier Lequeux's son Maxim, whose nationality was given as French American, also took an oath of allegiance.
Also very happy to gain citizenship was the family of Dunedin Hospital nurse Adewale Bamgbose, who emigrated to Dunedin in 2004 from Lagos.
"It's very good here. The people are nice."
The ceremony was an important ritual for him, his wife and three children, Mr Bamgbose said.
"When you gain something from a place, it's good to give something back."
