It's Not Baloney
Mortadella, ‘the most noble of all pork parts’ according to a proclamation of 1661, was so prized in the 14th and 15th centuries that it was used for currency, as noted in the contracts of the Cathedral Chapter of Bologna. The word comes from the mortar (mortaia) used by friars to grind the pork into a smooth paste, before kneading it with whole peppercorns and stuffing it tightly into its gigantic casing: the exact rules for its making were established with the Corporazione dei Salaroli (the sausage-makers guild) founded in 1367.
The Americans, who loved it, are responsible for much of the confusion over the name; after 1899 they were calling any kind of sausage ‘mortadella’ or just plain Bologna sausage, or 'baloney'. A lot of sausage made elsewhere that’s labelled mortadella might as well be baloney. A good mortadella must be made right, and sliced as thinly as possible; in the days before slicing machines, there were contests to see who could slice it thinnest and fastest.