What is a “motte” in a motte-and-bailey castle?

The story behind the answer

The motte was a raised earthen hill, often with steep sides, crowned by a wooden or stone keep. Its height gave defenders a commanding view and forced attackers to fight uphill, while the compact summit concentrated defenses around the most valuable structure.

This design spread rapidly after the Norman Conquest of 1066 because it was quick to build with local soil and timber, letting conquerors establish control points fast. The bailey—the enclosed courtyard at the base—held workshops, stables, and living quarters, protected by a palisade and ditch. Over time, many wooden keeps atop mottes were rebuilt in stone, and today many English and French towns still have prominent grassy mounds marking the sites of these early castles.