Kaspian sits next to 4 phonetic neighbors — Caspian, Casper, and Jasper are the closest matches by sound. Most share Kaspian's English-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"of the Caspian Sea"
"son of the rock"
"ascent, high"
"wisdom (Celtic symbolism)"
"dark one's town"
"clever, skilled"
"people's champion"
"place name: town in Pembrokeshire, Wales"
"son of Cadan, fighter"
"God is salvation (via Joshua/Hebrew connection)"
"settlement in the brushwood"
"from the British settlement"
"wheel maker, craftsman"
"God is worthy (via Jah prefix)"
"morning star (Venus before sunrise)"
"dealer, trader"
"noble, honorable"
"sun"
"who is like God"
"from the Lennox region of Scotland"
Similar sound: These names share phonetic patterns with Kaspian — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Persian origins, giving them the same cultural heritage as Kaspian.
Rhythm: Kaspian is a 3-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.