dkwiki is now dawiki
minnanwiki is now zh_ymin_nanwiki

rel13testwiki sounds like it's an old test wiki from REL1_13

sep11 seems to be deleted and ends up at http://wayback.archive.org/web/20030315000000*/http://sep11.wikipedia.org/wiki/In_Memoriam

l10nwiki might be an old translatewiki

wikidatawiki_old might be the "old" version before it was moved to s5

quotewiki is possibly now enwikiquote (https://quote.wikipedia.org -> https://en.wikiquote.org)

noboard is now noboard_chapterswikimedia

affcom is now chapcomwiki

langcom is now done on meta

quotewiki has no tables in it, so it was probably renamed to enwikiquote by running RENAME TABLE on all of its tables, but then the DROP DATABASE was not done.

Other similar wikis, probably with similar histories:

• minnanwiki has only an archive table, with zero rows
• demowikinews has only a searchindex table
• wikimaniawiki has no tables

There was a period in our history when anyone could create a wiki in any approved language in any of the approved sites, unauthenticated, by going to the URL and clicking the "create wiki" button which appeared on the "missing wiki" error page. I set up this system. It is possible that dkwiki, zh_cnwiki and zh_twwiki were accidentally created by this system, despite wikis already existing in the relevant languages. Any pages in those wikis would have been copied to the correct language codes, and then the wikis removed from all.dblist.

Wiki deletion has generally been done by removal from all.dblist, so that if the requester changes their mind for some reason, or if valuable data is in the wiki and needs to be recovered, the "deletion" can easily be reversed. The deleted.dblist file was set up by me as a way of documenting these deletions, but it has not been consistently maintained. It is not used by the code. So many of the wikis you list can just be added to deleted.dblist, specifically: dkwiki, zh_cnwiki, zh_twwiki, comcomwiki, langcomwiki, noboardwiki, rel13testwiki, sep11wiki.

Note that rel13testwiki appears to be a test wiki for MediaWiki 1.3, not MediaWiki 1.13.

wikidatawiki_old is large and recently created, I don't know where it comes from.

The wikimania database is not MediaWiki. Judging by the timestamps in the registration table, it was created for Wikimania 2005.

Change 102615 had a related patch set uploaded by Springle:
previously missed deleted wikis, bug 58680

https://gerrit.wikimedia.org/r/102615

Change 102615 merged by Springle:
previously missed deleted wikis, bug 58680

https://gerrit.wikimedia.org/r/102615

Dropped these empty ones: quotewiki, minnanwiki, demowikinews, wikimaniawiki.

As per Tim's suggestion, added these to deleted.dblist: dkwiki, zh_cnwiki, zh_twwiki, comcomwiki, langcomwiki, noboardwiki, rel13testwiki, sep11wiki.

Finding someone to knows about, and/or cares about, wikidatawiki_old...

Asked about wikidatawiki_old:

http://lists.wikimedia.org/pipermail/wikidata-l/2013-December/003271.html

Now dropped.