I remember when Deadwood debuted, I found the profanity really over the top. It did lead to the absolute genius of the Mr. Wu/Al Swearengen conversion that consisted almost entirely of cocksucker (surely one of the greatest moments of TV ever) but I wondered about the historical accuracy of the swearing. Well, check this link out:
This is a document warning baseball players in 1898 to watch the salty talk. The amazing part of it is that it lists examples of the sort of talk that will not be tolerated. These include such gems as, “A dog must have fucked your mother when she made you!” And to David Milch’s delight, “You cock-sucker!” Thanks, history.