Popular in Denmark

Celebrated in song—the rock 'n' roll classic "Louie, Louie"—this is a gregarious, friendly spelling of Louis not often used as a full first name. It reentered the US Top 1000 in 2015. It's a highly popular choice in England and Wales.

This name has been used in Denmark since the 13th Century, and is once again very popular there, now being in the Top 10. We don't see it crossing the Atlantic anytime soon, despite the strong meaning.

Marius, frequently heard in Germany and France, is a slightly fusty yet accessible name that has (Les Mis) to Anne Rice. With the rise in interest in such Latin names as Maximus and Atticus, Marius might start attracting more attention. Mario, the Italian, Spanish and Portuguese version of Marius, is much more widely used.

Mathilde is even more popular in France than Matilda, a hipster favorite thanks to Michelle Williams and Heath Ledger, is here. And the French pronunciation, while confusing to English speakers, makes it softer and prettier than the version we're more familiar with.

A sleek, smooth, understated name off the grid in the US but among the Top 100 girl names in Germany. In the US, it is a unisex name, while in Germany and the Netherlands, it is predominantly feminine.

Currently in the Danish Top 50, Milas blends the trendiness of Silas with the old-school bookishness of Miles. Milas might derive from Latin roots, meaning soldier, or from Slavic roots meaning great/powerful.

For those who can't bear to use a Kardashian name, perhaps the translation Nohr might be an option. Nohr is currently in Denmark's Top 50 and so is one of those Danish names prime to travel to the wider world.

Pelle is one of several possible Peter-related Scandinavian choices. In Swedish or Norwegian, the name Pelle rhymes roughly with Ella.

Apt name for a little drama queen with a long future ahead of her. Saga is a Top 30 girls' name in Sweden.

Ten years ago we would have advised people to steer clear of this name (and maybe choose the similar sounding Walter instead); but with the rise of other Nordic and Eastern European names like Viggo and Casimir, maybe its time to re-thing Valdemar. It's a big name, but with enough penache, it could be pulled off. Valdemar was introduced to Scandinavia in the 12th Century by a Danish king named for his Ukrainian grandfather, and is currently in the Danish Top 20.

Though to most Americans Viggo is a one-person name attached to intense actor Mortensen, it is actually an old Norse name dating back to the Vikings, and is currently the 32nd most popular appellation in Sweden. Viggo Mortensen is a Jr., sharing his name with his Danish father.

The way Wilhelm is pronounced anyway, so a pointless spelling variation.

From the land that brought us Viggo, we now have Villads. Not as punchy as the romantic sounding Viggo, but infinitely better than the name it derives from: Willehadus.