Historically, the modern organized religions like Judaism, Christianity, Zoroastrianism, Islam and Buddhism rose with the rise of Empires and became the State ideologies. These religions stamped out the earlier religious practices.
Religon of Ladakh Buddhism Archeological evidence shows that Ladakh was inhabited by people during the Neolithic age. Prior to rise of Empires, the pastoral life was the order of the world and each nomadic tribe followed its own religious cults of Shamanism, animism and ancestor worship. It is believed that Ladakh’s ancient religion was a collection of such practices till Buddhism promoted by the mighty Indian Empires spread in Ladakh through Kashmir and later to Tibet through Ladakh. With the rise of Islamic States, areas close to Kashmir was influenced by Islam.
So the major religion of Ladakh is Budhism and more than 77% population of Ladakh is Bhddhist followed by Muslim population around 14%. Prior to Islam, Hinduism dominated Kashmir and there are 8% Hindus too in Ladakh. British influence too percolated a bit through Missionaries during British rule and a few Sikhs from in Princely States of Punjab migrated to Ladakh. So 0.2 population each of Sikhs and Christians too occupy a small space in Ladakh.