http://www.korado-ryby.cz/eng/cenik_eng.xls

Bismarck herring are unskinned fillets that have been cured in a mixture of vinegar, sugar, salt and onions. Rollmops are Bismarck herring fillets wrapped around a piece of pickle or onion and preserved in spiced vinegar. Pickled herring (also called marinated herring) have been marinated in vinegar and spices before being bottled in either a sour-cream sauce or a wine sauce. The term can also refer to herring that have been dry-salted before being cured in brine. Kippered herring (also called kippers) are split, then cured by salting, drying and cold-smoking. Bloaters are larger than kippers but treated in a similar manner. They have a slightly milder flavor due to a lighter salting and shorter smoking period. Their name comes from their swollen appearance. Schmaltz herring are mature, higher-fat herring that are filleted and preserved in brine. The reddish Matjes herring are skinned and filleted before being cured in a spiced sugar-vinegar brine.

Matjesy s cibuli-slanecky, slaneckovy salat, which I would transalte as pickeled herrings.
You might find on restaurants menue also as Matjesy pork, so I would say Matjesy is derived from Matej.

This sort of herrings is quite salty but not sour as many of the above mentioned sorts are. They can be rolled (and filled with gherkin or onions or olives, but they are often plain. They are pink (but it is not salmon). They are typically served in Holland.