The oldest recipe known for a kind of tart is the italian
crostata (1465 by Maestro Martino*), which later was perfected by french cooks as
Tarte (prolly just to give a finger to the english cooks with their mastery of
pies that looked down at them before ; ) and the swiss
Wähe (1556)... the difference between pie and tart is mainly that the fruit topping isn't covered by pastry (->technical progress in oven construction)
I guess in the nordic and slavic countries it was more pancakes with berries (either baked in or topped with after baking),
Scone,
vareniki /pierogi, or
pâté in that days or maybe an early form of what we call
Danish pastry, ... we shouldn't forget that Cereal cultivation was only possible on a few high-lying areas back in those days with all the marshes and moors there ... i don't think ordinary people even dreamed of pies
*http://www.ucpress.edu/ebook.php?isbn=9780520928312
*https://books.google.ca/books?id=oF2jsqrWtEkC&pg=PR5-IA87&lpg=PR5-IA85
Vera, Strudel is a different dough, prepared different and the oldest known written recipe is from 1696 ...
