Track a list like History List

Question

I have a list; one of the columns is called "Assigned to" and the data which should be entered in this column should be Usernames. When we enter a username/usernames in this field, this item will be shown in that user's personal view of the list and assigned as a task to him; and this user too can assign this item or task to another one when he completed his role.
I want to create a list which take the track of the "Assign to" column; like a history that shows to which users this item is assigned to.
Can anyone help me?