In addition to the surge of inquiries from Americans, there was a big boost in registrations from people in predominantly Muslim countries. People from Pakistan — where nine of the victims were from — made 333 registrations after the attack, compared with 65 in the 10 days before it. People in Malaysia made 165 applications, compared with 67 in the period leading up to the attack.

Ms. Ardern has received widespread praise at home and abroad for her handling of the attack, including her decision to wear a hijab when visiting mosques and meeting the families of victims in the aftermath of the violence.

It was not the first time news events have prompted an interest in moving to New Zealand, a nation of roughly five million people. In the 24 hours after the November 2016 election of President Trump, immigration officials received 7,000 registrations from Americans interested in moving to there, and 17,000 during that whole month. Immigration New Zealand typically receives 3,000 expressions of interest from United States citizens each month.

Mustafa Farouk, the president of the Federation of Islamic Associations of New Zealand, said the families of the victims of the Christchurch attack had spoken about the country’s response in glowing terms, and he was not surprised that so many people were looking to relocate there.

Referring to the family of Mucad Ibrahim, a 3-year-old boy killed in the attack, Mr. Farouk said, “His father was telling me that he used to love New Zealand, but now he loves New Zealand even more.”