The title monarch in “The King and I” has dozens of spouses, but it’s clear who among them comes first. “Lady Thiang rules the roost,” Ruthie Ann Miles told me the other evening before a performance, as we discussed her character in the show, and just days before Miles received a Tony nomination for her performance. The actress said Lady Thiang’s “status allows her to advocate to the King on behalf of the other wives, just as it allows her to persuade Anna to go to the King late in the story.”

As a performer, Miles, who was born in Arizona, lived as a young child in Korea, and moved to Hawaii in the second grade, has long had an interest in playing powerful women. She spent her first two collegiate years at Southern Oregon University in Ashland, a city which is also home to the Oregon Shakespeare Festival. “I wanted to be Queen Elizabeth,” Miles said. But an interest in classical plays with such roles gave way to an interest in musical theater.

She went on to graduate school at NYU and a production of the musical Two by Two, whose composer was the same as that of The King and I -- Richard Rodgers. Other shows followed: Avenue Q off-Broadway, national tours of Sweeney Todd and Annie. But it was a starring role in Here Lies Love, a musical written by David Byrne and Fatboy Slim and given a 2013 production at New York’s Public Theater, that gained Miles wide attention as well a Theatre World Award and a Lortel Award.

In Here Lies Love, she played Imelda Marcos, the First Lady of the Philippines, which would seem a parallel of sorts to Lady Thiang, a kind of First Lady of Siam.  How do the roles compare? “Doing Imelda was harder than doing Lady Thiang,” said Miles. “Here Lies Love lasts only 90 minutes, but it was exhausting. I had to sing and dance in six-inch heels.”

What’s more, the two shows are vastly different in terms of music and sound. “As Imelda,” Miles said, “I was surrounded by a very different sonic set-up: 360 degrees of speakers. When they are staring you in the face it’s difficult to hear yourself sing.”

By contrast, Miles called The King and I a kind of “music therapy”: “You can really breathe while you are singing – the three hours fly by.” Miles added: “I really love telling Lady Thiang’s story. The musical shows a powerful woman who is very different than the one I played in Here Lies Love.”

Miles confessed that “I didn’t like taking Imelda’s emotional journey. The audience has turned on her by the end of every night. But you have to do your best to portray her as a protagonist.”

Lady Thiang exercises power much differently than does Imelda. “In this show, I can’t have an ‘off with their heads’ approach,” Miles said. “Lady Thiang can’t be jealous of the other wives. She has to be diplomatic.”  She must also, however, be realistic. “She knows,” Miles said, “that to save Tuptim’s life that Tuptim’s lover will have to be killed.”

As for the songs of The King and I, Miles said that to over-sing them “would be a disservice to Rodgers’ music and Hammerstein’s lyrics.” She explained: “The orchestrations and the melodies themselves do so much of the work for you. It may be a cliché to say it, but as a performer you must allow yourself to be the vehicle for what Rodgers and Hammerstein have written.”

As for Lady Thiang’s number “Something Wonderful,” Miles said she needed help at first in her approach to it: “I wasn’t sure how to do the reprise, which is a whole key higher.”  She got assistance from Ted Sperling, the production’s music director, and from Bartlett Sher, the production’s director.

“Bart said that when Lady Thiang does the reprise she is singing not just about her husband but about Siam. It’s not just about the King but about her country and her son.” Miles said that such suggestions helped her enrich the song. And I can assure you that this enriched interpretation is lovely every night: a powerful woman affecting an audience powerfully.

Brendan Lemon is the American theater critic for the Financial Times and the editor of