Apparently, the earliest messengers/prophets had appeared in these traditions. It started with the four sages, Agni, Vayu, Aditya and Angira, who transmitted and propagated the unworldly knowledge from the Creator God in the form of the four Vedas.
From the earliest time of human origin till about 10000 years back, Vedic culture was the religion, so to say, practiced in the world. The many historical incidents like, Arjun marrying a nāg kanya called ‘Ulopi’ from Pāthāl (America*), the belief of the Mosque at Mecca as an earlier temple of Shiva when King Vikramaditya was the ruler there and, Shakuni of Mahābhārath to be a resident of Gāndħār (Afghanistan), all clearly establish the ancient spread of the culture of Bhārath all over the world.
Though there can only be one Supreme Principle, unfortunately, most of the religions have conjured up their own divinities or gods as the Supreme Principle. Keeping aside the Supreme Principle for the moment, if we tread the paths of different religions dotted by each one’s characteristic traditions, beliefs and rituals and climb up the mountain top, we will end up with the concept of LOVE as the final pinnacle of religious glory.