For a millennium and a half, India was a confident exporter of its diverse civilisation, creating around it a vast empire of ideas. Indian art, religions, technology, astronomy, music, dance, literature, mathematics and mythology blazed a trail across the world, along a Golden Road that stretched from the Red Sea to the Pacific.

William Dalrymple draws from a lifetime of scholarship to highlight India's oft-forgotten position as the heart of ancient Eurasia. For the first time, he gives a name to this spread of Indian ideas that transformed the world. From the largest Hindu temple in the world at Angkor Wat to the Buddhism of China, from the trade that helped fund the Roman Empire to the creation of the numerals we use today (including zero), India transformed the culture and technology of its ancient world – and our world today as we know it.