The Chola Naval Empire
From southern India, the Chola dynasty did what almost no premodern Indian power did: it built a navy and projected force across the sea, raiding Srivijaya in Sumatra and taking Sri Lanka. At home it ran an unusually organized state, with local assemblies that elected village officials by drawing lots from pots, and it funded vast granite temples that still stand. Chola trade and Tamil merchant guilds carried Indian religion, script, and art across Southeast Asia — which is why Hindu gods appear on temples in Cambodia and Java.
The path or medium of exchange moves, and a place or power rises or declines because it sits on or off the new route.