Actor Willem Dafoe was cast in DC Films' "Justice League" movie in mid-April, but any details about his role had been hard to come by. Following a visit to the film's London set, we finally know that that Willem Dafoe will be playing Vulko in the upcoming "Justice League" film. But who is Vulko?

For a character who's been a constant presence in DC Comics' "Aquaman" titles for nearly 50 years, he's not exactly the first name of when you think of Justice League allies. Few know he was actually the king of Atlantis for more than a decade! With a rich comic book history to explore and a bright movie history ahead of him, it's time to get to know the Atlantean ally Dafoe will be bringing to life starting in late 2017.

Vulko made his first appearance in "The Brave and the Bold" #73 (by Bob Haney and Howard Purcell), when he helped Aquaman and Aqualad discover a whole other universe was hiding in a single water drop!

When Aquaman was then kidnapped by the evil ruler of this universe, Vulko, Mera, Aqualad and Aquababy had to turn to Aquaman's Justice League teammate, the Atom, to shrink down and bring Aquaman back!

After his introduction, Haney quickly brought Vulko over to the pages of the "Aquaman" ongoing series (which he also wrote) the very next month in "Aquaman" #35. Nick Cardy was the artist on that title, and it's very likely he began drawing the character before Vulko's official debut in "The Brave and the Bold" #73. It's possible Haney didn't much care what Vulko looked like, with "Aquaman" #35 showing see a very different looking Vulko (his name is also initially spelled with a C in "Aquaman" #35).

When Steve Skeates and Jim Aparo took over as the new creative team on "Aquaman" with Issue #40, they brought Vulko with them (using the Cardy design, but with a K in his name) and made him a regular member of Aquaman's supporting cast. Vulko appeared in nearly ever issue until the series ended.

Three years later, when Aquaman got his own feature starting in "Adventure Comics" #435, Vulko was along for the ride. He served a dual purpose of both being the go-to expert for all things scientific or medical, as well as being Aquaman's most trusted adviser. In 1977's "Adventure Comics" #448 (by Paul Levitz and Jim Aparo), Aquaman had lost his crown to the evil Karshon, but Vulko helped free his true king by imploring the people of Atlantis to believe Vulko, who had served kings before Aquaman, believed in Aquaman.

At the end of the issue, Aquaman actually decided to abdicate the throne and Vulko, of all people, became the King of Atlantis!

Vulko astonishingly remained the king of Atlantis for over a decade! It was not until 1991's "Aquaman" #1 (by Shaun McLaughlin, Ken Hooper and Bob Dvorak) that we saw Vulko was no longer King and is once again an adviser, but now to King Thesily!

Thesily's rule was quite brief. Soon afterward, Aquaman lost one of his hands in battle with the evil Charybdis. He had Vulko create a robotic harpoon in place of his missing hand in "Aquaman" #4 (by Peter David, Gene Gonzales, Martin Egelend and Howard Shum).

It was during Peter David's run that readers saw Vulko first challenge Aquaman, leaving his long-time friend behind after he became discouraged by some of Aquaman's decisions as a ruler. Eventually they reconciled and became friends once again. However, during the "Our Worlds at War" crossover in 2001, Aquaman had to protect Atlantis from an alien invasion, so he came up with a desperate plan that resulted in Atlantis being sent into the distant past. It didn't work out well for the Atlanteans, though, as they were given hard labor for fifteen years, which was revealed in the JLA crossover, "The Obsidian Age."

Once Atlantis returned, Vulko was among those that banished Aquaman as punishment for his actions. Once again, Aquaman and Vulko couldn't stay mad at each other and ended up becoming friends again. However, in "Infinite Crisis" #3, the Spectre was tragically turned against Atlantis -- and he destroyed the underwater city! In "Aquaman" #38 (by John Arcudi, Leonard Kirk and Andy Clarke), Aquaman confirmed that Vulko perished in the attack. Vulko was so dedicated to Atlantis, however, that his ghost even stuck around and helped out a bit.

Then the New 52 happened, and Vulko was once again a trusted adviser of Aquaman. In fact, in "Aquaman" #0 (by Geoff Johns, Ivan Reis and Joe Prado), it was Vulko who first informed Aquaman of his Atlantean heritage!

However, Vulko also had an ugly side to him. During the "Throne of Atlantis" crossover that began in "Justice League" #15 (by Geoff Johns, Ivan Reis and Joe Prado), a tidal wave hit Metropolis. Vulko saved Lois Lane's life and then told Superman and Wonder Woman that it was all the doing of Aquaman's evil brother, Ocean Master!

The League fought against the forces of Atlantis, with Aquaman stuck in the middle. In the end, the only way for Aquaman to stop the war was to take the throne of Atlantis for himself. When he did so, he realized that was Vulko's plan all along. He believed that the Ocean Master (King Orm) was so evil he had to force Aquaman into taking the throne from him, and the only way he could think of to do that was to start a war between Atlantis and the surface world by attacking both sides and blaming it on the other. Aquaman was shocked at the callous way Vulko was willing to sacrifice innocent lives for what he felt was the "greater good" and had his friend arrested.

However, during a storyline where the first king of Atlantis (the "Dead King") returned to retake his throne, Aquaman was forced to work with Vulko to stop the evil Dead King, and the two men even eventually came to somewhat of an understanding -- Vulko and Aquaman are just destined to not be apart for too long! [vulko23.jpg, vulko24.jpg] Expect to see Vulko pop up again in Aquaman's post-Rebirth ongoing series!

Are you excited for Vulko's role in "Justice League"? Let us know in the comments!