The Leh, Ladakh and Spiti valleys actually form part of the Tibetan plateau and the people who live there are close cousins of the Tibetans. Buddhism is the way of things here and in these stark, stone mountain deserts you need some kind of belief to keep a grip on things.
Life is hard in these desert valleys with little in the way of agriculture and winters that are so harsh as to cut them off from the rest of the country for half the year. Every spring the Indian army gets the ploughs out and tried to clear the road to allow tourism and commerce through. In Spiti, the practice of immersion is still sometimes practiced where a new born babe is held in an icy stream for a minute – if it survives then its considered strong enough to face the hard life ahead.
The valleys are spectacular and quite lunar in their appearance. Travelers follow the trail up from Manali or Parvati to Leh in July and August, heading back down again as the weather worsens in September. Consequently the locals have just a few months to make the most they can out of the strange aliens with Lonely Planets in their hands before facing the elements once again.
There’s good walking to be had and plenty of time to watch the local way of life as you gorge on apple pie in the local cafes. Read a book on Buddhism and get a little closer to the experience.