I once spent some months, in 1980, helping a butcher who was a friend. Part of my tasks (simple ones of course) were making burgers and sausages. Interesting work and his recipe must have been good as they sold quite well.
Amongst the sausages that I have enjoyed in the past were those which arrived, packed in lard, in tins during WW2. I believe we own thanks to the United States for them. It is a shame they are still not available here. The other sausages, only available in recent times in Supermarkets, are those made in Lincolnshire and the Fens. Whilst I like them my better half does not so they are rarely on the menu.