when did it begin?
Around the beginning of the Common Era (CE) following the reign of Augustus and his conquest of Egypt in 30 BCE.
Indo-Roman trade relations
antedated the southern trade route via the Red Sea and monsoons which started around the beginning of the Common Era (CE) following the reign of Augustus and his conquest of Egypt in 30 BCE.
which ports had trade links with south asian parts Arsinoe, Berenice and Myos Hormos. between whom did the trade take place? The Roman Empire and the Indian Subcontinent.
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Indo-Roman trade relations [SEP] Introduction
Indo-Roman trade relations (see also the spice trade and incense road) was trade between the Indian subcontinent and the Roman Empire in Europe and the Mediterranean Sea. Trade through the overland caravan routes via Asia Minor and the Middle East, though at a relative trickle compared to later times, antedated the southern trade route via the Red Sea and monsoons which started around the beginning of the Common Era (CE) following the reign of Augustus and his conquest of Egypt in 30 BCE. The southern route so helped enhance trade between the ancient Roman Empire and the Indian subcontinent, that Roman politicians and historians are on record decrying the loss of silver and gold to buy silk to pamper Roman wives, and the southern route grew to eclipse and then totally supplant the overland trade route.