What effects did Alexander's campaigns in northern India have on the population and its culture, as well as that of people further east?
I know that Indians and Greeks had some contact for centuries, however I believe this contact wasn't particularly strong. What did the Indians and people further east make of this powerful, Macedonian army marching all the way from Greece to India, defeating all the armies that it came against and subjugating civilizations? Did it change the native beliefs at all? How strongly did Hellenistic culture affect the native cultures?
Well we know of two kingdoms, the Indo-Greek Kingdom, and the Greco-Bactrian Kingdom, both of which were hellenized states but occupied regions of NW India, Pakistan, Afghanistan and at times other modern day countries in the area.
At some sites in India, we have hoards of coins which have both Indian and Greek designs, as well as a mixture of the languages. There was also an acceptance of Hinduism and Buddhism, and these religions were mixed into the Greek pantheon.
There are a few notable names from the Indo-Greek Kingdom, Menander I is one of the only people who appears in the Greek records, but also in contemporary Buddhist ones. [This is a useful journal] (http://www.jstor.org/discover/10.2307/623931?uid=3738032&uid=2&uid=4&sid=21103926132497), you can access through Jstor to give you a brief introduction on the topic, and it is where I drew some of my information from.
There are also some good books on the [coinage] (http://www.amazon.co.uk/Indo-Greek-Indo-Scythian-Coinage-Decline-Indo-Scythians/dp/0904173127/ref=sr_1_4?ie=UTF8&qid=1398518288&sr=8-4&keywords=indo+greek), which is one of the main sources for the Indo-Greek Kingdom, though the book in this link follows the later Indo-Greek Kingdom.