(1) Religious life in ancient India was originally very simple. But in course of time complex rituals and ceremonies began to dominate the practise of worship. Poor people were unable to observe them.(2) Caste system became rigid and it created inequality in the society.(3) Religious literature was in SDanskri. The common people spoke in Prakrit and Pali could not understand it.(4) The priestly class took advantage of it and interpreted religion according to their convenience.(5) People wanted a simple religion which would remove the evils in the society.

Factors responsible for the spread of Buddhism and Jainism:

1. Social and religious unrest:
- During the time when Buddhism and Jainism emerged, there was a growing dissatisfaction with the ritualistic practices and social hierarchies of the Brahmanical Vedic religion.
- The caste system and the exclusion of certain groups from religious activities created social unrest and led people to seek alternative paths.

2. Teachings and philosophy:
- Both Buddhism and Jainism offered a new approach to spirituality and focused on individual salvation and self-realization.
- Their teachings emphasized non-violence, compassion, and the rejection of material desires.
- These philosophies appealed to individuals who sought a more egalitarian and ethical way of life.

3. Charismatic leaders:
- The founders of Buddhism and Jainism, Gautama Buddha and Mahavira, respectively, were charismatic leaders who attracted large followings.
- Their personal presence and ability to communicate their teachings effectively played a significant role in the spread of their respective religions.

4. Monastic communities:
- Buddhism and Jainism both established monastic communities that provided a sense of belonging and solidarity.
- These monastic orders offered a structured way of life, where individuals could dedicate themselves to the pursuit of spiritual goals.
- The monastic communities also served as centers of learning and played a crucial role in disseminating the teachings of Buddhism and Jainism.

5. Trade and travel:
- The spread of Buddhism and Jainism was facilitated by the extensive trade networks and the movement of people across different regions.
- Traders and travelers who adopted these religions carried their beliefs to new areas, exposing more people to these philosophies.

6. Patronage by rulers:
- The patronage of rulers played a vital role in the spread of Buddhism and Jainism.
- Kings and emperors, such as Ashoka in India, embraced these religions and promoted their teachings.
- This imperial support provided resources, protection, and legitimacy to these religions, encouraging their growth and expansion.

7. Adaptability and assimilation:
- Buddhism and Jainism were flexible in adapting to local customs and traditions.
- As these religions spread to different regions, they incorporated local beliefs and practices, making them more accessible and relatable to the local population.

In conclusion, the spread of Buddhism and Jainism was facilitated by various factors such as social unrest, the appeal of their teachings, charismatic leaders, the establishment of monastic communities, trade and travel, patronage by rulers, and their adaptability to local customs. These religions offered alternative paths to spiritual fulfillment and provided individuals with a sense of purpose and community, which contributed to their widespread acceptance and growth.