Family are coming to Oamaru and Georgetown from England, Canada, Australia, Ireland and New Zealand for a reunion.
Sonny Macaulay said his great-grandparents, Aulay and Catherine Macaulay, arrived from Glasgow to Dunedin in 1874 aboard the SS Invercargill , with their 3-year-old son, Donald.
The weekend celebration would be the first to honour their arrival in New Zealand and would celebrate their Scottish heritage. About 60 were expected to attend.
"It will be interesting. I’m very much looking forward to it," Mr Macaulay said.
His niece, Kay Parker, who co-ordinated the family event, will host a function with husband Alan Turnbull on Saturday.
On Sunday, the reunion will gather in Georgetown, where the family have a long-standing presence, in the home of Mr Macaulay’s son, Avon, in what was the local school.
After Aulay and Catherine Macaulay arrived in 1874, they had spent several days in the "immigration barracks" before travelling to Oamaru on a "wee coastal ship" to settle in Georgetown, Mr Macaulay said.
They had seven children, the youngest of which, George Macaulay, was Sonny’s father.
He said the family reunion was "the first and probably the last", depending on future generations, and praised his niece for bringing everyone together.
"It wouldn’t have happened if it wasn’t for Kay and all her excellent knowledge ... She’s helped everyone keep connected," he said.
A cake with the family crest, made by Lois Miles, and haggis will be served at the function.