Below is a link to an interesting article providing a backstory to Yoga and how it has emerged in the current more physical form that we find it in this country.
It focuses purely on the physical teachings of Yoga however this if you have every practiced much Yoga you'll soon realise that this is just the tip of the iceburg. Yoga when taught well, skillfully uses body and breath to develop a still mind, and also offers a wealth of knowledge for self-development and wellbring through key texts such as Patanjali's Yoga Sutra (2000 years prior to this). The physicality and postures have emerged with influences from western culture and some classes this is more obvious than others. Some interesting video clips too. bbc.co.uk.bodybuildingandphysicalculturearticle>>>>>