The History Tab
To view the entire history of a Profile, just go to the Profile Page and in the top left you will see a History tab, it will load a list of changes with the newest change at the top.
You will see the date changed, who changed it and the fields that were changed.
As you scroll down, it will continue to load more data until you get to the beginning of the Profile.
You will require the Read Profile History permission. Administrators will get this automatically. If you are not an administrator, please speak to yours to be granted access.
History is limited to August 2019 when this new data first started recording. Beyond that, you will need to look at the Audit Log or contact support.
If you need to view changes made across the whole system rather than Profile by Profile you can use the Audit Log.