These Three Countries Are Winning the 'Game of Thrones'

Helen Sloane | HBO

Who's winning the "Game of Thrones?"

As the Lannister and Stark clans continue to fight to the death on screen, there are some clear winners on the other side of the cameras.

Millions of dollars are being pumped into local economies in Iceland, Northern Ireland and Croatia, where many of the HBO series' exotic settings are filmed.

"Game of Thrones," based on the best-selling "A Song of Ice and Fire" book series by author George R.R. Martin, is the story of seven feuding families fighting for control of the fictional Westeros kingdom. The series, full of sex, back-stabbing and bloody battles, was recently renewed for a fourth season.

Winterfell—Northern Ireland

Northern Ireland is the location where the woodsy, damp and dark scenes of the 'Winterfell' portion of the show are filmed. It is the home of the protagonists of the story, the Stark family.

An estimated $98.4 million has been pumped into the economy in Northern Ireland so far, according to estimates from Northern Ireland Screen, the government-backed agency supporting media production in the region. This estimate includes all the money spent on good and services over the past three seasons of the show so far.

Local film and television companies, sound stage builders, design teams, transportation companies and extras' talent agencies are all benefiting from "Game of Thrones" filming in the Belfast area, according to NIS.

HBO said there have been as many as 750 crew members working on filming, all at the same time, for shoots there.

The NIS staff is very excited about the fanfare and success of "Game of Thrones" and encourage the stimulation of the local economy. The agency hopes "Game of Thrones" will do for Northern Ireland what Peter Jackson's "Lord of the Rings" did for New Zealand.

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NIS estimates the upcoming fourth season could bring in another $30 million for Northern Ireland's economy, according to Moyra Lock, head of marketing for the agency.

Lock also told CNBC that NIS has provided $13.9 million in production funding to the show so far, investing more money with each season.

Helen Sloane | HBO

The show's filming comes at a time when the local economy could use an extra boost.

Northern Ireland is part of the United Kingdom, and U.K. GDP contracted at a rate of 0.3 percent in the fourth quarter of 2012, according to U.K. National Statistics service.

North of the Wall—Iceland

If you move north on the mythical Westeros map, to where all those freezing cold, snow-covered, miserable looking scenes 'North of the Wall' are filmed, you'll find yourself in Iceland.

HBO works with a production company based there called Pegasus that provided crews, extras, equipment and facilitated the shoots locally, according to the company's production manager, Einar Sveinn, .

Both HBO and Pegasus declined to provide CNBC with specific details about the cost of filming in Iceland.

Pegasus, however, said up to 250 crew, actors, and extras were working on the scenes there and 500 hundred rental cars were used during shooting.

Pegasus Managing Director Lilja sk Snorradttir said about 3,000 hotel rooms were rented over the period of shooting in the country. With each room costing a minimum of about $80 per night, that works out to a total of $240,000 spent just on hotel rooms in 2011 and 2012.