Can I customize the history grouping?
If I select Show All History, the history is grouped into TODAY, YESTERDAY, LAST 7 DAYS, THIS MONTH, LAST MONTH etc.
The first issue I have with this is that the groups are not mutually exclusive.... eg. I can't delete everything but TODAY and YESTERDAY because those sites are included in LAST 7 DAYS and THIS MONTH. The only point the history becomes exclusive is LAST MONTH.
If the grouping can't be mutually exclusive, then I'd rather just be able to show the whole history without any group, sort by date and then I can just scroll to the point I want to keep and delete everything below that point.
Wšykne wótegrona (2)
I think you will need to find an add-in for this.
The reason is that the History list is page oriented rather than visit oriented: it only shows the most recent visit to a page rather than all visits. If you click September, you probably will see some dates in October, too, when you revisited a page that you had visited in September. Since these are grouped together by page, wherever you view it, deleting a recent visit to the page probably will also clear the September visit, and deleting an October-dated entry under September probably will remove the more recent visit.
Maybe use the search bar in the Library (search for a colon) or set the sidebar to order by last visited date. Then you should be able to remove specific visits.
It is possible to create a specific place: query, but that may not be easy and obvious.
See also this NirSoft utility: