The Star Trek Universe has been known to tackle societal, political, environmental, and other types of issues throughout the history of the franchise. This one tackled the Vietnam War head-on, not only specifically pointing out the "20th-Century brush wars on the Asian continent", but also as portraying the Federation and the Klingon Empire as superpowers using an otherwise peaceful world as pawns in their struggle for power (a direct allegory of the Cold War at that time, between NATO and the Red Bloc).
(At around 17 mins) Is the first clear close-up ever of the Sick Bay panel. The vertical scales are, from left to right: Temperature - left scale in °F and right in °C -, Brain - K3 (unknown unit)-, Lungs - no units, but it seems to measure FRC (Functional Residual Capacity) in liters, Cell Rate - no units -, Blood - O5 (perhaps pressure) - and Blood - T2 × 10 (Blood transverse relaxation time - ms ×10). Center symbols: Top Circle "Respiration", second Circle "Pulse" then two legends: Adjust for Normal, Recorder.
The original writer of this episode, Don Ingalls, put the pseudonym Jud Crucis on it after Gene Roddenberry rewrote it. Ingalls' original contained many more overt Vietnam analogies than what finally appeared. According to Allan Asherman's The Star Trek Compendium this script referred to Apella as a "Ho Chi Mihn-type" and the tribesmen wearing Mongolian clothes. Though friends with Roddenberry since their days as LAPD officers, Ingalls did not like the changes, and the pseudonym was his wordplay on "Jesus Crucified."
Ned Romero appeared in the Star Trek: The Original Series episode "A Private Little War" as Krell, the Star Trek: The Next Generation episode "Journey's End" as Anthwara, and the Star Trek: Voyager episode "The Fight" as Chakotay's grandfather.
This episode features the last production credit for showrunner Gene L. Coon who resigned halfway through Season 2. His replacement John Meredyth Lucas struggled to come to terms with the show's unrelenting schedules and the budget cuts that Paramount was insisting on. NBC were also unhappy about the show's implications about sex, threatening the airing of a show that was already on the borderline of cancellation.