Complex sentence: Alvin was originally named Morgan by the town's residents in honor of the settlement's original resident, Santa Fe employee Alvin Morgan; upon discovery the name Morgan had been taken, the town named itself after Morgan's first name.
Split into simpler sentences: Alvin was originally named Morgan by the town's residents in honor of the settlement's original resident, Santa Fe employee Alvin Morgan. But upon discovery the name Morgan had been taken, the town named itself after Morgan's first name.