Gregory Silva (left) helps Vonda and Ray Thompson close a certificate of deposit (CD) at First Financial Bank on High Street in downtown Hamilton Friday, Aug. 16, 2013. First Financial celebrates in 2013 the 150th anniversary of the bank's founding in Hamilton. NICK DAGGY / STAFF The company has the 6th oldest banking charter in the U.S. First Financial's history dates back to the founding in 1863 of First National Bank of Hamilton, Ohio. In 1923, the name was changed to First National Bank and Trust Co. of Hamilton, and later First National Bank of Southwestern Ohio. Holding company First Financial Bancorp formed in 1983. The bank's corporate headquarters moved out of Hamilton, and the company is now based in downtown Cincinnati although it maintains the historic headquarters in downtown Hamilton. First Financial is still Butler County's largest bank by deposits.