It depends on where in the world and how long ago you consider to be olden days.
Mostly for the same reasons they happen today, over ownership of natural resources.
what were shops like in the olden days
yes they did have needles in the olden days
Please define "olden days" because each time had different things. To some people 1950 is the "olden days".
It means courageous or fearless. In the olden days this title was given to someone who performed extraordinary feats at wars.
Why was an oasis surrounded by a wall in the olden days
most people in the olden days
by many sages in the olden days
It is cheaper
Cupcakes were made from scratch back in the olden days. This means that all ingredients were added fresh and many recipes were verbally handed down.
what did thety wash their clothes with back in the olden days