The political map of ancient and medieval India was made up of myriad kingdoms with fluctuating boundaries. In the 4th and 5th centuries A.D., northern India was unified under the Gupta Dynasty. During this period, known as India's Golden Age, Hindu culture and political administration reached new heights.
Although today's Hinduism differs significantly from earlier forms of Indian religion, Hinduism's roots date back as far as 2000 BC, making it one of the oldest surviving religions. Because of its great age, the early history of Hinduism is unclear. The most ancient writings have yet to be deciphered, so for the earliest periods scholars must rely on educated guesses based on archaeology and the study of contemporary texts.
Though many Hindus have adopted the name for themselves, they also use the terms "Veda," or "Vedic religion," which refer to the ancient texts at the core of the tradition, or Sanatana Dharma (Eternal Law).
The Upanisads were recorded from 1000-600 BCE. The Ramayana and the Mahabarata were recorded between from 2nd century BCE to the 4th century CE. The Mahabarata describes three paths to salvation: the path of duties (karma-marga), the path of knowledge (jnana-marga), and the path of devotion (bhakti-marga). Though the Upanisads emphasized renunciation and asceticism, the later texts emphasize that the three paths can be used simultaneously for the maintenance of the world order (dharma) and release from the the world (moksha).
Religions in 1909
References The Coming Of Islam To South Asia http://history-world.org/islam6.htm