Darius sits next to 4 phonetic neighbors — Darian, Marius, and Arius are the closest matches by sound. Most share Darius's Persian-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"he who holds firm the good"
"fire (from the sun god Aodh)"
"son of Ridge"
"church official, rule of law"
"gift of God"
"wealth, fortune"
"powerful ruler of the home"
"to follow a course, leave a mark"
"help, helper"
"watchful, vigilant (via Casey influence)"
"son of Nicholas (via Cole)"
"charcoal, dark"
"western enclosure"
"ruler of the people"
"lover of hounds, hound-desiring"
"divinely appointed, called by God"
"son of"
"the twin"
"son of Neil, son of the champion"
"made by God"
"passionate, fiery one"
Similar sound: These names share phonetic patterns with Darius — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Old Persian origins, giving them the same cultural heritage as Darius.
Rhythm: Darius is a 3-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.