Account history captures all changes made and related to an Account including, Account group assignments, Customer assignment, Splits and Assigned rep. It will also display the value that was added or modified, the date, and the person who made the change.
Accounts Account >> More >> History
When in the account, click More on the top left corner. In the More menu, select History.
In the History menu, you will see the changes made to the account since its creation. This includes but it not limited to, the account assignment, account merges and customer transfers. This also includes the date a change was made, and by whom.