It's a makeover year for ­Campbell Mithun, the Minneapolis ad agency that has been part of the marketing landscape regionally and nationally for more than 80 years.

For starters, the 230-employee shop has a new name. Starting this week, the agency will be known as Mithun, in honor of co-founder and advertising legend Ray ­Mithun.

Second, Mithun is getting new digs. Early next month, the agency will move five downtown blocks from its Campbell Mithun Tower location on S. 9th Street to the rehabbed site of the first Federal Reserve building in Minneapolis at 510 Marquette Av. S. The relocation gives the agency a chance to design its own state-of-the-art office space.

Then there's the addition of new clients in the last year, including Pandora, Zoosk, ­Ashley Furniture and Blue Cross and Blue Shield of Minnesota.

And there's been change at the top of Mithun's leadership structure. It began 15 months ago when Rob Buchner, an alum of the ­Fallon ad agency, was named CEO to replace Steven Wehrenberg, who left Campbell Mithun after 31 years to pursue an ­academic career.

Since Buchner took over, the agency has added a new executive creative director, two associate creative directors, a group media director and three associate media directors.

The new logo for Mithun, the Minneapolis ad agency that is the one of the nation's largest and works for clients such as General Mills and Toro.

"This has been a well-run agency that always makes money, but it was conservative and low on innovation and dynamism in some ways," Buchner said in an interview. "We want an agency recognized nationally as a creative voice. We want to embrace where we came from."

Campbell Mithun was created in 1933 during the Great Depression by Mithun and co-founder Ralph Campbell. The first clients were Land O'Lakes, which remains a client today; Northwestern National Bank, which eventually merged with Wells Fargo; and Andersen Windows.

The agency was quickly known for its drive and creativity. In 1947, it created the "Land of Sky Blue Waters" slogan for St. Paul-brewed Hamm's beer that would resonate with Minnesotans for generations. Fourteen years later, Campbell Mithun would provide the fledgling Minnesota Twins with the theme song, "We're Gonna Win, Twins."

After Campbell died in 1949, Mithun ran the agency on his own. By 1953, Campbell Mithun was the largest agency in Minneapolis with billings of $15 million. By the early 1980s, billings reached $250 million a year and Campbell Mithun was the largest ad shop west of the Mississippi.

With a series of mergers engineered by then-owner Saatchi & Saatchi, Campbell Mithun briefly became known as Campbell Mithun Esty, and billings topped $1 billion a year.

Mithun, who died in 1998, received advertising's top honor in 1989 when he was inducted into the American Advertising Federation's Hall of Fame.

"He was a taciturn, innovative, scrappy guy who really made the agency what it became," said Wehrenberg, the former CEO who is now an advertising professor at the University of Minnesota.

But Campbell Mithun was slow to change with the times and unable to attract the kind of young talent that was bringing awards to other agencies.

"For years, it was always the premier agency in town. It was the biggest and most nationally recognized," said John Purdy, a retired advertising instructor at the University of St. Thomas who spent 15 years at Campbell Mithun.

"But times changed faster than the agency could adapt, and it lost some of its luster over the years."

Buchner said it made sense to change the agency's name to coincide with its move to a new location.

"Agencies come and go and this one has endured," he said in an interview. "This name change is meant to give us a new recognition. It's a revitalization."

In the new world, Mithun has embraced an advertising formula called "creative sciences" that uses analytics and psychology to drive marketing strategies.

"Data is such a big part of everything," said David Carter, Mithun's executive creative director. "We are embracing the analytics piece.

This isn't the first time Campbell Mithun considered changing its name. Wehrenberg said it was explored when he was CEO several years ago, but the timing didn't seem right.

But pairing the name change with another seminal moment for the agency — in this case a physical move to a new location — seemed to make sense.

With David Carter, chief creative officer, behind him, Rob Buchner, Mithun CEO, talked about their new office space.

"It's been under consideration since I came here 15 months ago," Buchner said. "This is an agency that has been conservative by choice, and we want to go forward more confidently. Creativity is all about risk."