Rodgers & Hammerstein were pioneers when it came to combining social issue theater and spritely musical riffs — humming about racial equality and women’s rights? That was a thing in the 1950s? It was, for them at least.

Issues of social justice are front and center in The King & I, now at the Winspear through New Year’s Eve. In 1862, while Victoria is extending her empire from the tiny spit of land called England and Abraham Lincoln is fighting to keep his country together in the midst of a war over slavery (yes, that’s what the war was about), the autocratic King (Jose Llana) of the Southeast Asian nation of Siam (now Thailand) struggles to enter the age of modernity. He come from a tradition where polygamous among royals is de rigueur, where nobody’s head may be higher than the potentate (even if he’s sitting on the floor), where women are as fungible as a bowl of rice and his pronouncements, no matter how wrong, must be accepted as gospel. (Sound familiar?)

But the King also recognizes that his world is dying, and science and progressivism are necessary for human advancement — he knows, for instance, that the world was not created in six days, but eons. (Funny, that; someone tell Jeff Sessions.) So he recruits a British widow, Anna (Laura Michelle Kelly) with a tween son, Louis (Rhyees Stump), to serve as schoolteacher to his 67 children. (What is it with R&H, governesses and dictatorial dads with big broods?) She’s enlightened for a Victorian — opposed to slavery, in favor of love over arranged marriage, disgusted by the humiliating groveling the King requires. She soothes his heart (and does so without marrying him), and Siam becomes poised to exert its own independence from European colonization.

The King & I is probably R&H’s most glamorous production. The sets and costumes are luxe and the cast of 32 fills the stage. But it’s also a weighty confrontation between equals — a woman who stands up to a King on principal and defends the rights of others. At the center of Act 2, in fact, sits an elaborate, gorgeous ballet, a Buddhist reinterpretation of Uncle Tom’s Cabin (rechristened The Small House of Uncle Thomas), that takes up the better part of a half-hour and stands as a metaphor for authoritarianism gone amok. This production, directed by Bartlett Sher and choreographed by Christopher Gattelli (after Jerome Robbins’ original), gets to the meat of that message; as usual, I still get chills during “Shall We Dance,” a spritely polka that in Rodgers’ hands feels more like a frenzied waltz. Indeed, this show is populated by some of the duo’s best songs; it’s a garden of delights for a coloratura, which Kelly revels in: “Hello, Young Lovers,” “Getting to Know You,” of course “Shall We Dance.” She does an amazing job acting the role as well, hidden under yards of gabardine and Victorian primness.

Equally wonderful is Llana’s King. He exaggerates the humor in the role, milking even unexpected laughs, but also delves into the King’s humanity, his conflict, his self-doubt. And the ending of the show, always one of its weakest elements, feels earned and organic for the first time. Joan Almedilla as Lady Thiang, pictured, wows the audience as well on her big number.

We all know R&H for the beauty of their work, and this production, which won four Tonys in its recent Broadway revival, proves it. But for a show written more than 75 years ago, what stands out is how The King & I still feels remarkably relevant.

— Arnold Wayne Jones

Now through Dec. 31 at the Winspear Opera House.