A dazzling account of the trade that enriched the subcontinent and allowed Romans to enjoy fabulous clothes, ivory, emeralds – and a dash of pepper

At the height of the Roman empire, after its conquest of Egypt in 30BC, luxurious Indian goods suddenly became available to Europeans in unprecedented quantities. No one could resist them. So much gold and silver flowed away to India to pay for these things, grumbled Pliny the Elder, that the subcontinent had become “the sink of the world’s most precious metals”.

At a time when the yearly wage of a Roman soldier was about 900 sesterces, Pliny, a Roman miltiary commander and author, estimated that Indian merchants were annually draining the empire of at least 55m sesterces. He would have been horrified to know that, in fact, Indian imports into Egypt at this time were probably worth over a billion sesterces a year. Indian museums are said to hold more Roman coins than any other country outside the former empire.