Why is Diwali not celebrated on a large scale in Kerala?

That's an interesting question and to my knowledge there is no definite answer here. Perhaps history buffs can answer you more accurately. read more

Kerala was somewhat geographically isolated from the rest of India until part of it was colonised by the British. So there has not been any large scale cultural exchanges with the rest of India. In fact Kerala had more cultural exchanges with Central Asia, Far East, the Chinese and Romans than rest of India. read more

Unlike the rest of India, Diwali is not a major festival of Kerala. But, in recent times it is gaining popularity among the Kerala-ites. Diwali is celebrated in Kerala in the same manner as the northern states of India, but at a much lower scale. read more

Dont know why Kerala does not celebrate Deepavali I personally think Kerala is always unique in its celebrations (because Onam the top most festival of Kerala is celebrated primarily only in Kerala and No other Indian state). Yes Andhra Pradesh/Telangana and Karnataka also dont celebrate it on a huge scale.on par with Tamil Nadu.. read more