Montana sits next to 4 phonetic neighbors — Monty, Savannah, and Santana are the closest matches by sound. Most share Montana's Spanish-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"mountain, mountainous region"
"of God, God's own"
"supreme ruler"
"father of peace"
"lord, father, sovereign"
"supplanter, one who replaces another"
"to tame, subdue"
"invented name; possibly son of the fearless one"
"son of Peter (son of the rock)"
"brave power"
"man from Sebastia"
"safe, unharmed (proposed etymology)"
"rocky cliff, crag"
"follower of Dionysos, of Zeus"
"warrior, battle"
"consecrated by augury"
"son of Dubhagan (little dark one)"
"town near the cliff"
"hound of the plain"
"young dog, whelp (strength and loyalty)"
"the Nubian, dark-skinned"
Similar sound: These names share phonetic patterns with Montana — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Latin origins, giving them the same cultural heritage as Montana.
Rhythm: Montana is a 3-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.