Final answer:
The Aryan and tribal migrations significantly impacted the Indus Valley by introducing a new social order, evolving religious practices, and economic changes. They altered the course of its existing urban culture, setting the foundation for future civilizations in South Asia, including the development of Hinduism.
Step-by-step explanation:
The significance of Aryan and other tribal migrations on the Indus Valley civilization lies in the cultural, economic, and social transformations they brought with them. The Harappa and Mohenjo-Daro societies were part of an advanced urban culture with an elaborate system of drains, orderly streets, and distinctive structures. After their decline, the Indo-European speaking Aryans migrated into the region, introducing a new social structure and religious beliefs that were influential in the development of Hinduism.
The interconnection between the Dravidians, who are thought to be earlier inhabitants of the Indus Valley, and the later arrivals of Aryans, led to significant changes in the economy, politics, and society. The Aryans brought with them domesticated horses and knowledge of iron, which changed warfare and agriculture in the region. They also introduced the caste system and Vedic religion, shaping the future social and religious fabric of Indian civilization.
Artisans in the Indus Valley created intricate sculptures and jewelry, showing a rich cultural life that was carried into subsequent societies. Trade routes extended from the Indus Valley to far-off regions, indicating a wide sphere of economic influence. All these factors combined to influence later Indian civilizations, leaving a lasting legacy on the subcontinent's history which is still apparent in many cultural norms and practices in South Asia today.