Harlan sits next to 4 phonetic neighbors — Harlen, Harley, and Carlan are the closest matches by sound. Most share Harlan's English-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"rocky land, stony ground"
"speckled, freckled"
"ruler of the people"
"handsome, beautiful"
"descendant of the sun god"
"supplanter"
"crooked valley"
"always king"
"selected, chosen"
"descendant of the sea warrior"
"sweetheart, dear one"
"ever awake"
"three, the third"
"asked for, prayed for"
"peace, complete"
"he who holds firm the good"
"fire, flame"
"the great river"
"ruler of the world"
"heathland, open moorland"
"fire (from the sun god Aodh)"
Similar sound: These names share phonetic patterns with Harlan — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Old English origins, giving them the same cultural heritage as Harlan.
Rhythm: Harlan is a 2-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.