I love this quote about where Argonians & Khajiit came from

...the thing that really stood out was the eight playable races – which ranged from three human and three elf races to the more exotic Argonians and Khajiit. "I used to love the old Sinba movies and fondly recalled some of the stop-motion creatures they would fight", Lakshman reflects. "For some reason, the word Argonian stuck with me (from Jason and the Argonauts) and I equated that to exploration. What's at the farthest reach of your mind and the world? In my mind, there be dragons, hence the Argonians being reptilian."

That explains the humanoid reptiles, but what about the less obvious nod to The Eye of Thundera? "With the Khajiit, I'd spent a lifetime as a practitioner of the martial arts", Lakshman explains. "I've trained for 30 years, was a nationally ranked black belt and competed in over 1200 combats in the ring. I knew I wanted to make a feline race, and I saw their grace and agility as an intrinsic quality, much like a martial artist. In Japan, the art of the sword is called Kenjitsu [sic]. I modified that to become Khajiit, and thus the race of these highly nimble and agile felines was born!" And as the series progressed, the Khajiit became more cat-like in appearance.

-- 2014 Interview with Vijay Lakhshman, The Making of Elder Scrolls: Arena