Follow me in merry measure.

While I tell of yuletide treasure.

At the Minnesota Historical Society, where state archivists protect and preserve more than a century of Christmas memories.

There, you’ll find delicate Victorian glass ornaments. Hand-painted Christmas cards. An embroidered Hmong nativity scene. A festive Dayton’s gift box. Norwegian Julebukkers mugging for the camera behind their holiday masks.

Many of the treasures are archived online for anyone who wants to see how Minnesota used to celebrate Christmas: Christmas carolers from 1945. Christmas dinner, 1908. An 1870s Christmas tree, surrounded by wooden toys. Holiday decorations at Donaldson’s department store, 1955. A smiling mail carrier loaded down with holiday cards from 1924. Newsboys crowding in for the 1925 Minneapolis Journal Christmas party.

“We have hundreds of holiday cards,” said Sondra Reierson, curator of 3-D objects at the Minnesota Historical Society. “Some Christmas ornaments. … A lot of holiday-themed marketing for local events and businesses — everything from Winter Carnival to the Pillsbury doughboy in a Santa hat.”

But the latest addition to the museum’s Christmas collection is really going to make things merry and bright.

A Santa suit.

But not just any Santa suit.

In all his long years as Santa Claus, Leo Treadway, a second-generation Santa Claus in a beautifully embroidered, fur-trimmed suit, greeted each child with a question — and it wasn’t whether they’d been naughty or nice that year.

“How have you helped somebody this year?” Santa Leo would ask the children who climbed on his knee, sometimes clutching pages-long wish lists, complete with pictures they’d cut out of toy catalogs. “The whole purpose was to get them to think less about themselves and what they wanted, and more about other people.”

It was a thoughtful question from a Santa who put a lot of thought into his role. He inherited the work ethic from his father, who used to pull on a Santa suit, climb into a helicopter and drop onto the roof of the five-and-dime store in their New Jersey hometown.

Treadway, now of St. Paul, wore his father’s old suit when he started playing the role of Santa 30 years ago. When he decided he needed a new suit of his own, he worked with Lynn Farrington, a costume designer from Macalester College’s theater department, to create something museum-worthy. The fur-trimmed red velvet coat weighs 25 pounds, and Treadway insisted on authentic details — from the real pockets on his suit to the real beard on his chin.

Children, he said, know a fake when they see one.

If all they see is “just a man in a red suit with a false beard,” he said a few days before Christmas, it takes them out of the magic of the moment. He had only a few minutes with each child, to make a connection, to remind them that Christmas is supposed to be about giving, not getting.

How have you helped somebody this year?”

If a child couldn’t think of anyone, Santa had a follow-up.

“Who do you think are the people who need help?”

People who fled from wars, the children would suggest. People who are sick. People who are homeless. People who don’t have enough to eat.

All of them need help, and Christmas comes only once a year.

“For me, that is the primary message of what Santa is all about,” Treadway said. “Getting them to think, ‘You know, I bet there are other children who would be so happy just to get one gift.’ ”

When it came time for Santa Leo to hang up the suit and retire, he decided to donate it and another marvelously detailed costume — a Joulupukki outfit, covered with Finnish embroidery, the sort of thing Santa might wear around the toy workshop in the off season.

Reierson said the staff is working to preserve and catalog the outfits so they can be displayed next Christmas. Archivists will probably build a mannequin especially for the suit. That’s something they’ve done for only one other outfit in the collection — Prince’s “Purple Rain” costume.

Sometimes, the children had questions for Santa Leo, too.

Is Santa real? Was he the real Santa?

Yes, Virginia, Minnesota. There is a Santa Claus.

“I’m the real Santa if you believe that in your heart,” he would tell them. “Santa has lots of other Santas who help him and I’m one of those. But I’m still Santa.”