One of the iconoclastic boys of the beach has his roots in the land of polar fleece and mukluks.

Tommy Bahama, the menswear mainstay known for loosefitting silks and palm-tree graphics, grew out of an idea that Minnesota clothing executive Bob Emfield roughed out on a yellow legal pad with a colleague.

Starting with a character description of an island guy who never had to go back to work, they built the brand into a $500 million business that gave aspiring, paunchy, middle-aged American dudes the thumbs-up to wear a casual shirt untucked.

Emfield came up with the name, and Tommy Bahama appeared 20 years ago this month.

“It just came to me,” he said. “I wanted it to have an island feel, and ‘Tommy Bahama’ had a nice tintinnabulation.”

Emfield, a man whose tanned skin and casual attire seem at odds with his immaculately trimmed silver hair and mustache, has retired from the day-to-day details of the company. But he still sometimes attends sales meetings and remains the walking, talking, relaxing embodiment of his co-creation.

In the late ’80s, Emfield and his Generra clothing associate Tony Margolis crafted their character as if they were amateur novelists — a leisurely man of casual tastes whose deceased parents left him a coconut planation, who smoked Rocky Patel cigars, drank Red Stripe, and drove a vintage Volkswagen bug convertible with water skis and casting rods in the back.

Everything from what he ate to whom he dated was written down and filed away. Just one important facet of his character was forgotten: what he wore.

After an especially trying week at Generra, Margolis asked Emfield, “Do you still have the stuff on the island guy?”

Emfield, the visionary, and Margolis, the orchestra leader/marketer, added another founder, Lucio Dalla Gasperina, as the tastemaker and designer. Dalla Gasperina took the island guy and imagined what the man with the “life is one long weekend” motto would wear.

What makes the brand work, said Wendy Liebmann, CEO of WSL Strategic Retail, is that you can wear a Tommy shirt in Minnesota that can transport you to the Florida Keys. “Everything from the fit to the fashion makes people feel happy wearing it,” she said.

Tommy was one of the first menswear brands to adopt vanity sizing, where a guy who usually wore an extra large could fit into a large. “It’s what the brand is all about,” said Mary Brett Whitfield, senior vice president at Kantar Retail. “Making customers relax and feel good about themselves.”

Despite Emfield’s love of Minnesota, he and his cohorts never had Tommy wearing skiwear or fleece, although the brand has since expanded to four-season clothing. In fact, the Midwest continues to be one of the company’s most consistent markets.

It started when Midwesterners would see the clothes in specialty, surf and pro shops when they were on vacation, Emfield said. “Then they’d go back home and ask their local men’s store why they didn’t carry Tommy Bahama.”

The original store and adjoining restaurant were in Naples, Fla., and the first shops to carry the line in the Twin Cities were the Foursome in Wayzata (now in Plymouth) and Hubert White in downtown Minneapolis.

The Foursome still carries the full line of Tommy Bahama. It’s the store’s biggest seller in sportswear, according to Scott Winterbottom, general merchandising manager at the Foursome. “We’re probably their largest single store account in the Midwest.”

Winterbottom likes the way the brand has stayed true to its roots, but manages to attract a somewhat wider demographic.

What started as a brand for Florida or Palm Desert has become a more-general symbol for a relaxed lifestyle. Emfield described the customer as a guy between 45 and 65 who has a boat or loves boating, belongs to a country club, and whose wife may be younger than he is. He’s a bigger guy who’s a little overweight and out of shape, he said.

Emfield is the brand’s unofficial walking, talking model, said Brad Sherman, vice president and general manager at Hubert White. “You never see Bob without a tan, and you never see him wearing a necktie,” he said.

Hubert White sold the Tommy line early in its history but dropped the line when it became a licensing empire. Oxford Industries of Atlanta bought the company in 2003.

The clothing sells well because it fits everybody, even the little guy, Sherman said. “Big guys love it because it covers them and makes them feel good,” he said. “It is one of the first modern successful brands besides Ralph Lauren that went to a complete lifestyle collection.”

Parts of that collection, which now includes indoor and outdoor furniture, rum, ceiling fans, umbrellas, scents, glassware and bedding, as well as men’s and women’s clothing, is now in the Mall of America store, Nordstrom and more than 100 stores worldwide, not to mention Emfield’s home on Lake Minnetonka.

“It’s all Tommy stuff in the house,” said Emfield’s wife, Laurie.

In retirement, Emfield, 71, lives the Tommy life full-time, whether in Minnesota or Florida. On Lake Minnetonka, his 31-foot Skiff Craft sports a rich, mahogany interior and a red flag on the stern that says “Relax.” On the deck captain’s chairs, it’s “Life is one long weekend.” His waterfront property is filled with sailfish, palm trees and starfish motifs.

“I am Tommy Bahama,” said Emfield. “Or he became me. We all became him,” said Emfield of himself and his two co-founders.

“He’s in all of us Minnesotans, if only when we’re taking a winter vacation in Aruba or grilling out on the deck in the summer.”