The seals found in indus valley civilization has shown people worshiping a meditating man( pashupatinath or Lord shiva ) and a bull ( Lord shiva devotee nandi bull is worshiped by hindu) http://indus-valley-civ.weebly.com/religion-and-culture.html What are your views about it
There's certainly more to say, but you may be interested in one of my older answers to a similar question