Re: Persians
I though Butt came from Bhat , Hindu Brahmin name. There are Bhat also in Kashmir. Many Hindus were converted to Islam when it came to Kashmir.
Were all Persians , Zorostrians before they were converted to Islam?
Today most of the Zorostrians are in India.
Yes most of the Persians were Zoroastrians. Greater Persia including Khorasan, followed Zoroastrianism. After the arrival Islam particularly Shiism, they migrated to India/parts of Pakistan.
As for Kashmir, it is pretty much the abode of the Aryans. Whether they are from Persia or not is highly debatable.