Well it was some high elf dude but then he got himself killed and raised into undeath, so now its Arthas Menethil, Former Crown Prince of Lordaeron, Former Knight of the Silver Hand, King of the fallen Lordaeron, First of the Lich King’s Death Knights,Champion of The Scourge, Lich King of the Scourge.
Edit: Tev would never say “Don’t be like my Dad” IC. It’s just convenient shorthand.