This iris is named for the Dutch engraver and nurseryman Emmanuel Sweerts (1552-1612), most famous for a Florilegium published shortly before his death in 1612. 2
1 Discussion by participants on the iris@hort.net mailing list http://www.hort.net/lists/iris/mar05/msg00005.html
2 Netherlands Institute for Art History http://www.rkd.nl/rkddb/(ym0ugh2yckwx5e4514sftnf0)/dispatcher.aspx?action=search&database=ChoiceArtists&search=priref=360858