Governance, trade and thinkers

With so much war, every powerful king needed a big army — soldiers' pay, weapons, horses, elephants, and in parts of the north, camels to carry supplies. That cost a lot, so kingdoms needed an efficient administration to collect tribute from vassals and taxes from traders.

One new idea came with Muhammad Ghūrī: a more centralised system, giving officers temporary land assignments in return for collecting revenue and serving in the army. 'Temporary' is the key word: an officer who can be moved cannot build up his own power base.

Despite the turmoil, India's trade with China and Southeast Asia kept growing. Coins and pottery from those lands have been found all along India's west coast, which had many ports and shipyards building sea-going ships.

But the backbone of the economy was still agriculture, as it is today: rice and barley in the Ganga plains and Bengal, saffron from Kashmir, spices from Kerala, ginger from Bengal, wheat from the northwest, and cotton from western India and the Deccan.

A thriving economy meant thriving arts, literature and science. The Chālukya king Someśhvara III wrote the Mānasollāsa, an encyclopaedia covering astronomy, architecture, music, medicine, cooking and games — a complete guide to royal life and government, stressing a king's duties to his people. At Khajuraho, the Chandellas built dozens of temples, including the Kandariya Mahādeva and Lakṣhmaṇa temples.

Rāmānujāchārya of south India was a philosopher-saint who challenged Ādi Śhankarāchārya's advaita vedānta. His school, viśhiṣhṭādvaita vedānta, holds that the world and individual souls are real, and that bhakti and surrender to God are the path to liberation. Where Śhankarāchārya called the world māyā, Rāmānuja called it real.

Basaveśhvara (Basavaṇṇa) was a royal minister at Kalyāṇī who gave up his post to become a social and religious reformer. He founded the Lingāyat movement, which rejected caste distinctions and empty rituals, and taught personal devotion and honest work. He judged people by their inner worth, not their rank, and taught that men and women have equal spiritual potential. His short Kannada poems are called vachanas. At Kalyāṇī he set up the Anubhava Maṇḍapa, a 'hall of experience' where men and women of every background could meet and discuss all aspects of life.

India's influence reached far. Angkor Wat in Cambodia, built in the 12th century by the Khmer king Sūryavarman II, is the largest religious monument in the world. It was first dedicated to Viṣhṇu, with inscriptions in Old Khmer and Sanskrit and huge carvings of the Rāmāyaṇa and Mahābhārata; its five great towers stand for Mount Meru. The book's lesson for the whole period: resilience in the face of conflict, and the lasting power of knowledge, learning and creativity.