Spoiler alert: If you aren't caught up on your Game of Thrones viewing, there may be a few surprises inside.

Even though it's summer in Washington, D.C., winter is coming along with a new season of Game of Thrones. In honor of this occasion, the staff of the National Numismatic Collection have chosen a selection of coins representative of the noble houses of Westeros.

House Stark: Winter is Coming

After so many weddings, deaths, and resurrections of those raised in House Stark, it can be hard to remember that the thing that makes the Starks particularly Starky is their connection with the North— especially the direwolf, a large, rare species of wolf. The Stark's sigil (seal or signet) is a gray direwolf on an icy, white field, which underscores the significance of the Stark children's unusual, sometimes mystical, partnership with their direpups. Another invaluable partnership between wolf and man can be seen on the reverse of the Urbs Roman, a coin of Constantine I. The reverse of the follis depicts the infants Romulus and Remus being suckled by a she-wolf. The two sons of Mars were kept alive thanks to the wolf, without whom Romulus would have died and Rome would never have been founded. Perhaps, in Romulus-like fashion, there is hope for a great kingdom ruled by the first family of the North.

House Targaryen: Fire and Blood

Daenerys Targaryen has spent the Game of Thrones saga making a name for herself—several, actually: the Mother of Dragons, Khaleesi of the Great Grass Sea, Breaker of Chains, and more. She harnesses the power of fire and blood, renowned for her skills as dragonlord and evidenced in the sigil of her house, which depicts a red three-headed dragon on a black field. The silver-haired Targaryens are not alone in their veneration of dragons as ancestral symbols of power and prestige. This gold liang coin depicts a mighty and ferocious dragon flying through clouds toward the viewer, flames protruding from its mouth. The coin was minted under the Guangxu Emperor of the Qing dynasty, where the dragon would have been understood as a symbol for wisdom, power, nobility, and ambition. Such symbolism is literally used by Targaryens and their dragons to claim rule of the Seven Kingdoms.

House Frey: We Stand Together

As we have learned from many seasons of Game of Thrones, you did not want to mess with House Frey, particularly not their leader, Walder Frey. Does the Red Wedding ring any bells? Another historic leader you didn't want to mess with was Trajan, who ruled the Roman Empire from 98 –117 AD. The sestertius coin shown above was minted under the rule of Trajan and features a portrait of Trajan. The reverse of the coin shows a bridge vaulted over the river Danube with a tower on each side. Similarly, the sigil of the House Frey is a bridge between two towers. One of Trajan's most gainful conquests was that of Dacia on the northern side of the Danube River. However, this territory was later abandoned as it was difficult to defend, much like the Stark family was abandoned by their allies during the Red Wedding.

House Baratheon: Ours is the Fury

The stag, or male deer, has been featured heavily on heraldry, coats of arms, and coins from around the world. Stags are considered to be the kings of the forest and the protectors of all other animals in the forest, so it is no wonder that it features on the sigil for House Baratheon, which became the ruling house in Westeros after Robert Baratheon led a successful rebellion. This taler coin featuring a stag was minted in the German State of Stolberg. Stolberg was first established around 1000 AD as a mining town. Many precious metals such as iron, copper, silver, tin, and gold were extracted from the region. However, much like the now extinct (as far as we know) House Baratheon, the German State of Stolberg as depicted on this coin is no more. Its borders were absorbed into the surrounding municipalities, like Baratheon's queen, Cersei, absorbed his power when she became a Lannister ruler.

House Mormont: Here We Stand

Bears have often been used as symbols of power, courage, might, and virility. This franc coin was minted in Appenzell, Switzerland (not on Bear Island, the ancestral home of House Mormont). The Appenzell coat of arms, like the House Mormont sigil, features a rearing, ferocious bear. In 1403 Appenzell rebelled and seceded from St. Gallen, another Swiss state. On Appenzell's coat of arms . . . let's just say there is no mistaking the sex of the bear featured. An error by a printer from St. Gallen in 1578 that removed the particular appendage was deemed incredibly insulting, and quite nearly sparked a conflict. War was avoided after an apology was made and every copy of the offending image was destroyed. It's hard to say what Lady Lyanna Mormont, the current ruler of House Mormont, would think, as she has proven that women can be just as fierce as their male counterparts.

House Lannister: Hear Me Roar!

The Lannisters are known for many things—power, status, ruthlessness, close family relationships—and for being the wealthiest family in Westeros. Their sigil, a rampant lion, conveys their ferocity and royalty. Like the Lannister sigil, the lion dollar coin bears the image of a rampant lion. The lion dollar (leeuwendaalder in Dutch) was first minted in the Dutch provinces to finance a war against Spain, a neighboring power—something with which the Lannisters are familiar. A popular coin for the purpose of foreign trade, lion dollars circulated from the late 1500s to the early 1700s throughout Europe, the Middle East, and even colonial America. With Daenerys and her dragons approaching, I bet the Lannisters wish their influence reached as far across the Seven Kingdoms as the lion dollar reached around the world. Though they may not have been using lion dollars in Westeros, the Lannisters always paid their debts.

House Tyrell: Growing Strong

The Tyrells, led by Lady Olenna Tyrell—probably the toughest grandma ever—have had their share of rumors, schemes, and deaths. The Tyrell sigil, a golden rose on a green background, is complemented by their motto "Growing Strong." At a time when the American colonies were "growing strong," the Rosa Americana coin was being circulated. These coins were created for use in Ireland and the American colonies, though they were not popular in Ireland. This twopence Rosa Americana from 1722 features a Tudor rose, which is very similar to the Tyrell rose, on the reverse. The use of the Tudor rose design was a subtle insult to King George, who was unpopular in England and Ireland. There are many variations of Rosa Americana coins; they were redesigned more times than Margaery Tyrell was married.

Hillery York, Jennifer Gloede, and Emily Pearce Seigerman are collections staff in the National Numismatic Collection but secretly would like to work at the Iron Bank of Braavos.