Old National Insurance has agreed to buy the assets of Mutual Underwriters Insurance of Louisville. The transaction is effective Feb. 1, and terms were not disclosed in a news release. Mutual Underwriters owners Courtney Ball and Frank Rassiga will join Old National Insurance's operations in Louisville, according to the release. Mutual Underwriters' portfolio consists primarily of commercial and personal property/casualty accounts. Old National Insurance is a subsidiary of Evansville, Ind.-based…