Paudel is a poorbiya brahmin surname(i.e. brahmins traditionally occupying the eastern section of Nepal), versus Kandel, which is of Kumai or paschime origin. Conventionally speaking, Kumai surnames originate from Kumaon, Uttaranchal, and as such, most names(if not all) that Kumai bahuns have can be found in the Uttaranchal area. This is not so for most purbiya surnames, although exceptions exist. For example, Paudel, even though it is traditionally an Upadhya bahun surname, is a surname that is quite commong among Uttaranchalis. So is also the case for Pokharels, who are also Upadhya brahmins. I surmise that Paudels and Pokharels found in the hilly regions of North-Western India are basically Upadhya bahuns of Nepali origin who settled there when Nepalis ruled the territories in question. However, note this point. Many Kumaonis are of South Indian origin. You might want to visit websites dedicated to Uttaranchal culture, if you would like to learn more about last-names like Kadel, for instance. There are two major division of brahmins in Uttaranchal: 1) of Khas origin and 2) of mostly South Indian origin. There are also some surnames that originate from the Kashmir area, and of course some of Punjabi origin, although these are quite rare. Regarding the Khas, these were people of indo-european origin( although, by no means ARYAN, which refers to a certain group of people, specifically Punjabis. Take note that many opine that Kashmiri brahmins aren't of Aryan origin either), who occupied region from all the way to Southern Kashmir to North-Western Nepal. Also, let me mention that Nepali has traditionally been called Khaskura, aka language of the Khasas, aka language of Upadhya brahmins, in essence. So, in essence, what I think is that Upadhya brahmins are of Khasa origin, and indigenous to Nepal, versus Kumaos, who are more of Indian origin. Now, Pahadi dialects are divided into three principle origins: 1) Western(Southern Kashmir/Himachal Pradesh) 2) Central(Uttaranchal in essence) and 3) Eastern, which is basically Nepali. Curiously, some people are of the opinion that Nepali has similitaries to Gujarati languages. It's quite amusing. You may be familiar with Gujjars, a nomadic tribe of people, who wander around in the NWFP-Kashmir-Himachal-Uttaranchal area. I wonder whether they have any links to Gujaratis. Now Gujjars by no means look like your stereotypical Indians. They in fact look more like Afghans, many of whom in fact have reddish beard(without the dye, that is). I don't know what to make out of this, though. Then again, there is another theory that many Brahmin Peshwas from Maharastra fled to Nepal during wars with Muslims. These Peswhas are called Kokanastha brahmins, who can actually be traced to Afghanistan. Many of these actresses like Madhuri Dixit, Aditi Gowitrikar, etc are of Kokanastha origin, and are almost of white hue, in terms of skin color. Many of them, because of their blue/green eyes are disparagingly referred to as "cobras" by the more darker people of other origins. This is all I have been able to figure out as of yet. Of course, my theories might have innumerable inaccuracies.