The Dothraki language may not have the smooth, pleasant notes of High Valyrian — but the forceful tongue of the Khals and Khaleesis is undoubtedly a vital element in the unfolding plot of Game of Thrones.

The language was created in its earliest form by George R.R. Martin, the author of A Song of Fire and Ice — the book series the hit HBO show is based on.

But how does an invented language come to be?

"There are many, many steps along the way. And of course these kinds of things always start with an innovator," David Peterson, a language expert and creator, told Brent Bambury, host of CBC's Day 6.

Based in California, Peterson is one of the few people worldwide earning a living inventing fictional languages. He is also responsible for the High Valyrian heard spoken in the Free Cities on the show. 

Peterson says invented languages are a foundation of many fantasy epics, and the legendary J.R.R. Tolkien, author of The Lord of the Rings trilogy and its prequel, The Hobbit, was the person who took them to a whole new level.

"In this case, the innovator was Tolkien ... He was the first one to think it might be fun to just create a language, it might be cool. And it might add something to a greater work," Peterson said. 

To develop Dothraki, Peterson had only to return to the original source material to formulate the language.

"The place that I started was the books. We take George R.R. Martin as canon, very seriously. So I wanted to start there to be sure all the words he created in the books made it into the final version of the language," he said.