Complex sentence: The bank opened in Atlanta under the name "Atlantic States Bank" and expanded very quickly throughout Georgia, Florida, and Texas, in just five years after its opening they changed their name to Ironstone Bank to better accurately reflect their existing culture and demographics.
Split into simpler sentences: The bank opened in Atlanta under the name "Atlantic States Bank" and expanded very quickly throughout Georgia, Florida and Texas. Five years after its opening it changed its name to Ironstone Bank to more accurately reflect their existing culture and demographics.