A time period used for the scheduling of Reading Lists and the understanding of historical grammar.  The period is broadly considered to be that time starting at the time of the Church, and lasting until the New Heaven and Earth.

In more common use, the period can be described as the time between St. Augustine and Martin Luther theologically, Aurelius and Renee Descartes epistemologically, between the fall of Rome and the fall of Constantinople politically.  The Medieval period occurs between the Ancient and Modern times.

The Medieval period is further divided into the early (400 – 1000 AD, high (1000 – 1200 AD, and late middle ages (1200 – 1500 AD) .