Traditionally "Mincemeat" was used as a method to preserve game and meats that were just about to go bad. Later mincemeat became more of a culinary dish especially in the British Isles but elsewhere as well as the reach of England spread around the world. Mincemeat would use the likes of beef, lamb, sheep, goat, etc. Basically any meat that needed preserving. Basically they would cover portions of meat in a fat (suet mostly I believe) to help preserve it. When the meat needed to be used, it would be chopped up into fine pieces and added with fruits and nuts and cooked down. This would be the filling. Then the filling could be placed in jars where when cooled, the fat would create an air tight barrier for longer preserving. The filling would be used for pies and tarts as needed.
I personally love a traditional mincemeat pie. But I don't care for most of the stuff today as people have too little fruit and no meat. Now...maybe I will have a TSC mincemeat pie tradition for the holidays as well as my fruit cake tradition!
Here is a good concise article on mincemeat pies.
BEST Traditional Mincemeat
Few people today know what authentic mincemeat tastes like and they're missing out! Learn how to make the BEST traditional mincemeat!
www.daringgourmet.com
And a couple a bit more historical.
Mincemeat Pie History
Unfortunately, most people have never tasted a true old-fashioned mincemeat pie (also called mince pie). The flavor of real mincemeat pie (not the bottled version purchased at your local store)
whatscookingamerica.net
The strange and twisted history of mince pies
The sweet and spicy fruit mix encased in crumbly pastry has been a Yuletide treat for centuries – though its earlier incarnations might not be so tasty to modern tongues.
www.bbc.com