Jonatan sits next to 3 phonetic neighbors — Jonathan, Nathan, and Yonatan are the closest matches by sound. Most share Jonatan's Spanish-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"God has given"
"Italian form of Paul"
"stone of the flank (kidney healing)"
"shining army"
"supplanter (via Jacob/James)"
"fruitful, fertile"
"gift of God"
"horse-loving"
"reborn, born again"
"crown, wreath of victory"
"eager for battle"
"famous ruler"
"protector of men"
"Romantically associated with the poet Lord Byron meaning noble and ..."
"of Mars, dedicated to Mars"
"rulers advisor, mighty counselor"
"lord, elder"
"of the doorway god Janus"
"sun, lord"
"army friend, honorable companion"
Similar sound: These names share phonetic patterns with Jonatan — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Hebrew origins, giving them the same cultural heritage as Jonatan.
Rhythm: Jonatan is a 3-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.