It is famed for a love of singing and a passion for rugby. It has a distinctive Celtic language and is the birthplace of the poet Dylan Thomas. But few would claim that Wales, a nation of three million people outnumbered by sheep, is well known for whiskey, or whisky, as it is known in Wales.

Yet the country has played its part in distilling history — a Welshman is considered one of the founding fathers of bourbon — and a recent revival of whisky production has prompted new rules governing which liquor can call itself Welsh.

That was how the problems began in Abergwyngregyn (pronounced ABER-gwin-gregin), in the shadow of the ice-capped Snowdonia mountain range, where Aber Falls single-malt whisky is produced in a distillery filled with the strong malty aroma of barley.

Made with exclusively Welsh grain and water from a picturesque nearby waterfall, the light, slightly fruity, single-malt whisky distilled by Aber Falls was the first in more than a century to be produced in North Wales.

The packaging is red — one of the national colors of Wales — and bears an image of a dragon, the country’s symbol. When the distillery opened in 2017, its mission was to create “a Welsh brand, supporting Wales and collaborating with other Welsh businesses,” said Carole Jones, its general manager.

But it still was not Welsh enough.

Last year, Aber Falls whisky failed a test for certification as a protected Welsh product because the bottling was taking place not at the distillery, but 50 miles across the border, in England. The company had a choice: move the bottling back to Wales, or banish any mention of Welshness from the label — even the red dragon.

That, said Ms. Jones, would have been a “catastrophe” for Aber Falls, so by September, bottling was back on Welsh soil, allowing the company to join a list with four other certified Welsh whisky makers.

Awkward though it was, the wrangle over provenance highlights the growing interest in whisky in Wales, where a small number of commercial distilleries have followed in the footsteps of the best-known modern day producer, Penderyn. In total, Welsh whisky firms generate an estimated 23 million pounds, or about $29 million, in revenue a year.

Though for some, whisky is synonymous with Scotch, Wales enjoys an unusual place in liquor history because a Welshman, Evan Williams, is hailed as one of the first distillers of bourbon in the United States.

Historical details are sketchy and disputed, but, according to Heaven Hill Brands, the producers of a bourbon named for him, Mr. Williams was born in 1755, immigrated to North America in the late 1770s or early 1780s, and began distilling in 1783 in Louisville, Ky. He was probably raised in Dale, Pembrokeshire, where his family may have had a distillery.

The country he left behind never developed commercial production on the scale of Scotland or Ireland, but in 1889, one large producer, the Welsh Whisky Distillery Company, was founded in Frongoch, near Bala, around 50 miles from Aber Falls.

It did not survive long. In England, the whisky’s reception was lukewarm. In Scotland, it was cooler, and in Wales, social forces were gathering against it, including the temperance movement.

“Conditions in many of the factories and mines were so bad, and poverty was so rife, that there was a movement to galvanize people into Christian communities,” said Alexander Langlands, an associate professor of history at Swansea University. “In hard-working working-class communities, you really didn’t want young men, fathers and grandfathers, and women in the family, taking to the bottle. So there is a reason why it died — a cultural reason — here in Wales.”

It took a century, but the revival began in 2004, when Penderyn was opened in South Wales. It expanded a decade later and has won critical acclaim.

“It’s a whisky I would keep in my collection,” said Vic Cameron, a whisky lecturer at the University of the Highlands and Islands in Scotland, referring to a Penderyn single malt finished in a former Madeira cask.

While “Scotch took over the world,” Mr. Cameron said, whisky can be produced wherever cereals grow.

“If you ferment it and distill it, it’s whisky,” he said. “And the Welsh have everything that we have: They have decent water, they have malted barley, and they have yeast, so they can make good whisky.”

Still, selling whisky, said Dr. Langlands, who advised Penderyn on branding, often requires creating “a sort of mystique.” He said, “You really do need to pull on some sort of heritage.”

To that end, Penderyn uses an old copper works in Swansea, while Aber Falls, on the banks of the gushing river that flows from the waterfall to the Menai Strait, distills in a 19th-century slate works (previously used as a margarine factory).

Starting with a staff of only five, Aber Falls now employs 35 people, 29 of whom work at the distillery, with the remainder in Bangor, about 10 miles away, where bottling now takes place.

Spirits were first produced here in 2018, but whisky must be matured in casks for at least three years, so it was not until 2021 that a single malt was released.

Last year, still adapting to its exit from the European Union, Britain introduced a system of “geographical indicators” intended to replace a pan-European system meant to protect products like Champagne and Cognac from imitations.

Aber Falls supported the new rules that required that Welsh water be used and that the whisky be distilled, matured and bottled in Wales. But it fell foul of them when staff shortages made bottling in Bangor uneconomical and Aber Falls began turning to a site owned by its parent company in Chorley, England.

With the coveted “Welsh” designation at stake, the company moved swiftly to resume bottling in Wales, aided by the closure of a local factory that freed up more workers.

Business is good, and last January, the company moved to 24-hour distilling. Around 6,000 bottles of whisky are produced each week in Bangor, and exports go to 40 countries, including China and Kazakhstan, with plans to add the United States next year.

In the summer, there are as many as seven tours of the distillery a day, drawing many of the thousands of tourists who visit the spectacular Aber Falls waterfall. Some of them are whisky aficionados. Others come for other reasons.

“It’s something to do, particularly if it’s raining,” said Steve Bell, 65, a part-time tour guide.

Ms. Jones, the general manager, is 52 and was born and raised in Wales. She said there was now a big push by the government “to build Wales’s brand” — including gaining global recognition for its whisky.

That may pose a bit of a challenge.

Ms. Jones said she believed her single malt competes with those from Scotland, but she acknowledged that, after missing out on a century of distilling, Welsh whisky lacked renown.

“I think we still have a lot of work to do,” she said. “There are still people in a lot of countries who don’t know where Wales is.”