Aeron was possibly a minor Celtic god of war, and is definitely a river in modern-day Wales.

Aeron

Arthur, once the shining head of the Knights of the Round Table, is, after decades of neglect, now being polished up and restored by stylish parents, inspired perhaps by the new generation of royals. Arthur has led the list of possible names for the young British princes, chosen as a middle name for Prince Louis, son of William and Catherine, Prince and Princess of Wales.
 In addition to its leading role in the Arthurian legends, Arthurs figure prominently in Nathaniel Hawthorne's The Scarlet Letter, Edgar Allan Poe's The Narrative of Arthur Gordon Pym of Nantucket and George Eliot's Adam Bede. There are also countless Arthurs in children's literature, movies, and TV -- including The Fonz of Happy Days fame. More recently, Arthur was the son of Mr. and Mrs. Santa in the eponymous movie Arthur Christmas.
 Arthur has many notable namesakes, including playwright Arthur Miller; writer/astronomer Arthur C. Clarke; writers Arthur Conan Doyle, Arthur Rimbaud and Arthur Koestler; philosopher Arthur Schopenhauer; conductor Arthur Fiedler; and tennis great Arthur Ashe, the first African American to win the U.S. Open. Queen Victoria's seventh child was Prince Arthur.
 Arthur was a Top 20 name from at least 1880 through 1926. And in 2011, actress Selma Blair named her son Arthur Saint.

Arthur

Aegon

Aemon

Aerys

Areo

Arys

Beric

Brandon, a forebear of the Braden-Caden pack, had a great run of popularity over several decades, being in the Top 10 from 1992 to 1998, one of its inspirations being hearthrob Brandon Walsh played by Jason Priestley on the original Beverly Hills 90210--and it was aso the name of several soap opera characters. 
 Newer names like Landon and Braden are feeling fresher to many parents, and it's sometimes confused with the Irish Brendan.

Brandon

Balon

Barristan

Bronn

Brynden

Cleos

Dayne

Strong but gentle Irish last-name-first. Could bring to mind long-running rock group Duran Duran. 

Doran

Davos

Drogo

Formerly in style limbo, Edric has recently started to see more use by parents. It could be because it sounds medieval yet accessible - which George R. R. Martin took advantage of for several characters - or because it's an offbeat alternative to the more popular Ed-names.

Edric

Edwyn

Variant of Eamonn, itself a form of Edmund

Emmon

Eddard

Edmure

Euron

Gerold

Two prominent literary namesakes make Gregor a somewhat risky choice. On the highbrow side, there's Gregor Samsa, the Kafka character who woke up one day to find himself turned into a cockroach. And then there's Gregor Clegane, one of the most feared and purely evil characters in the world of Game of Thrones. It's a shame, because this earlier form of Gregory, quite common in Scotland, would otherwise make an attractive choice.

Gregor

Garlan

Gendry

Hoster

Howland

Illyrio

Ilyn

A Hispanic classic that has lost some momentum in recent years. It could be misunderstood by some as Jamie -- which is how it's pronounced on Game of Thrones.

Jaime

King Joffrey Baratheon, the petulant biological son of siblings Cersei and Jaime Lannisters, is perhaps the most notorious villain in the entire Game of Thrones canon. His name is practically a byword for sadism among fans of the show and George R.R. Martin's books. As such, we think it's probably a name best avoided IRL.

Joffrey

Streamlined version of the classic boys' names, sometimes a short form of Jonathan, which is in fact an entirely different name from John attached to a different Biblical personage. Jon feels more modern than the traditional John, but some may find it an overly slight variation on an already slim name. Jon Snow is a popular character on HBO's Game of Thrones.

Jorah, a Biblical name with a lovely nature-related meaning, might make a fresher alternative to the overused Jordan. It's similar to the feminine Nora, Cora, and Laura, but depending on your viewpoint, that may be an advantage. Jorah Mormont, often called Jorah the Andal, is a major character in HBO's Game of Thrones, marked by his loyalty to the woman he considers the rightful Queen of Westeros, Daenerys Targaryen.

Jorah

Jaqen

Jeor

Jojen

Kevan

Lothar is cloddish, till you add a dashing io to the end... 

Lothar

Lyonel

Lancel

Loras

Has a slight aura of danger, from its being two types of weapons and a looming character in the Star Wars films. Best left as a nickname for Mason. 

Mace

Martell

Mance

Ned is a gently old-fashioned Nancy Drew-Bobbsey Twins-era short form for Edward that sounds cooler than Ed and is enjoying a small style renaissance.
 Usage of Ned in literature goes back to a Ben Johnson character in 1614, and it is also the name of the protagonist in James Fenimore Cooper's Ned Myers. In Australia, Ned Kelly is famous as a larger-than-life legendary outlaw figure. In this country, Ned Rorem is a respected modern composer.
 There was a 1990s sitcom called Ned and Stacey, and other Neds have appeared in The Simpsons (neighbor Flanders), Groundhog Day and School of Rock. Ned Stark is a prominent, and unusually heroic, character in Game of Thrones, giving the name some new cultural cache, though we can't recommend using his proper name, Eddard.

Oberyn

Olyvar

Petyr

Podrick

Quentyn

A surname occasionally used as a first, as in former attorney general Ramsey Clark. This spelling is now closely associated with the psychopathic Game of Thrones villain Ramsay Snow (later Ramsay Bolton), and so is probably best avoided as long as the show and books are popular.

Ramsay

Raynald

Rickard

The version of Rob used in George R.R. Martin's A Song of Ice and Fire books and HBO's Game of Thrones.

Robb

Robert was the Number 1 boys' name in the US in both 1925 and 1950, and in fact was in the Top 25 for more than a century, giving it true classic status. Strong if not quite stylish, Robert remains in the Top 100 for baby boys as a family favorite.
 
Robert was derived from the ancient Germanic name Hrodebert, from the elements hrod, meaning "fame" and bertha, "bright." Robert was the name of three kings of Scotland, including Robert the Bruce, who freed Scotland from English rule. The name was brought to England by the Normans.
 Nicknames Bob and Bobby are stuck in the past, while Rob, Robb and Robby/Robbie have an ever so slightly more modern appeal. Antiquated pet forms Dob, Hob, Rab and Rabbie might be fresh nicknames, but the most fashionable form of Robert today is....Robert.
 There are countless literary and real-life namesakes, from poets Frost and Burns to actors Redford and De Niro to Shark Tank businessperson Robert Herjavec. Modern parents might consider honoring an ancestral Robert by choosing Robertson or Robinson, or even the derivative Robin, rising in popularity for boys.

Robert

Renly

Rhaegar

Rickon

Rollam

Roose

Despite a possible pronunciation problem, a pleasant, unusual choice. Sandor Clegane (nicknamed The Hound) is a major character on Game of Thrones.

Sandor

Samwell

Stannis

Stevron

Syrio

Theon, an ancient name attached to a noted Greek teacher of mathematics and astronomy, also father to the first woman mathematician, might appeal to parents in this field. You can think of Theon as Theo with something a little extra. Theon is also the name of a major character in Game of Thrones -- albeit a rather notorious character, Theon Greyjoy, who is known as Reek after undergoing months of brutal torture at the hands of sadist Ramsay Snow.

Theon

Just like Sam and Ben, Tom could be revived as a simple, well liked name on its own. Tom, just Tom, is one of the <a href="https://nameberry.com/popular-names/france">Top 100 Boy Names in France</a>

Tyrell is kind of part Tyrone or Tyler, part Terrell, but less than the sum of those parts.

Tyrell

Tyrion is one of the many new names entering the lexicon thanks to George R. R. Martin, author of the Game of Thrones book.  Tyrion's name shares its first two letters with those of his father Tywin and his grandfather Tytos.  The Tyrion Lannister character, a dwarf, is played by award-winning actor Peter Dinklage.  Martin has said he saw the Tyrion character as being both the ugliest and the most intelligent person in the world, a mixed legacy for any child.

Tyrion

Thoros

Tommen

Tywin

Varys

Victarion

Viserys

Walder

Common in Holland, the appealing Willem (as in de Kooning and Dafoe) makes William fresh and distinctive.

Willem

Willas

Yoren

allij28's list "A Song of Ice and Fire: Male" of 82 great name ideas: Aeron - Yoren!

A Song of Ice and Fire: Male

Names of male characters from George R. R. Martins A Song of Ice and Fire