Final answer:
Hinduism, which originated in the Indus River Valley about 4,500 years ago, is the world's oldest religion. It developed from the Vedic period's focus on rituals to incorporate a vast array of deities and spiritual practices, influencing and absorbing aspects of Buddhism and Jainism, and entrenching the caste system as part of its social framework.
Step-by-step explanation:
Hinduism, the oldest religion in the world, originated approximately 4,500 years ago in the Indus River Valley, which is part of modern-day northwest India and Pakistan. This religious tradition arose contemporaneously with ancient Egyptian and Mesopotamian cultures. Hinduism has no single founder and is a complex amalgam of various beliefs, traditions, and philosophies. Hindu scriptures include the Vedas and the Upanishads, with epic narratives such as the Mahabharata and Ramayana consolidating its mythological and philosophical ideas.
The Vedic period, identified with the compilation of the Vedas around 1500 BCE, represents one of the earliest phases of Hinduism. During this period, priestly teachings emphasized rituals and sacral knowledge passed down by gurus. Over the centuries, the religion evolved, incorporating elements from other traditions and establishing an elaborate pantheon of deities to appeal to a broader audience.
Hinduism's growth was also shaped by its interactions with Buddhism and Jainism, which emphasized spiritual practices such as meditation and the concept of non-violence. These interactions broadened Hinduism's spiritual practices to include yoga and meditation. Furthermore, the caste system, originating among Aryan peoples, became a significant aspect of Hindu social structure.