The Silk Road, the ________, and Trans- Saharan Trade:* silk road is largest trade network overland at this time, and is more prosperous when ruled by one single empire at a time (Abbasid, Mongol)* Causes of the Growth of Trade: Increased demand for luxury goods in Europe caused by the Christian crusades.Improved transportation technology like the magnetic compass, travel caravans, travel saddles being invented, the Chinese invention of the Rudder & Junk Boat.Unification and protection under the Mongol Empire.