With assets of $1.1 trillion, J.P. Morgan Chase & Co. is the product of a string of mega-mergers, including its $59 billion acquisition of Chicago’s Bank One in July. In 2000, J. P. Morgan and Chase Manhattan merged. Prior to that, Chase had combined with Chemical Bank in 1995 and Chemical Bank had merged with Manufacturers Hanover Trust Co. in 1991. Nash said that when she meets employees at the bank she can almost always tell if they came from J.P. Morgan, Chase, Chemical, or Manufacturers Hanover. “The toughest thing to do is get people to act like leaders in the new organization and let go of their heritage,” she noted.