Do you know if the following is correct?

In Northern India Hindus celebrate Diwali to mark the triumph of Lord Ram over the demon Raksah. Does this refer to the fight they had when he kidnapped Sita?

In Eastern India Hindus celebrate Diwali for a different reason, which is to honour the Goddess Kali destroying Bakasura (demon). What is the story behind this if it is correct?

In Southern India Hindus celebrate Diwali for yet another reason which is to commemorate Lord Krishna killing Narakasura (demon?). Again, what is the story behind this if it is correct?

Hindus in general? Do they celebrate Diwali because the rightful heir returned to the throne after being expelled to the forest for 14 years by his step mum who wanted her son to be King? Thus the celebration isn't so much to do with the events which occurred when they were in the forest but rather it's about them returning.

Is any of this accurate? help me get the correct information.

Thanks
HRM