If you were to do a search - you would find that
The date chosen for Yorkshire Day is August 1st and that it is
'a modern celebration - started in 1975'
So much for the 'history' of Yorks. Day!
Let's cross over the border of the Pennine chain which is also called the 'backbone of England'.
"Lancashire Day commemorates the day in 1295 when Lancashire sent its first representatives to Parliament by King Edward I of England to attend what later became known as The Model Parliament".
Lancashire's observance of their day is a lot older and has a ceremony attached.