The toponym is derived from the Old English but the site has been occupied since the Roman occupation of Britain, when the fortress town of Cunetio stood at an important road junction on approximately the same site. No remains of this fortress are now standing, but are clearly visible on aerial photographs. The Cunetio Hoard of Roman coins was discovered here in 1978. The name of the River Kennet, which runs through Mildenhall, is thought to have been derived from the Roman name, which is also used on the village's coat-of-arms.