Please explain the Byzantium era.

Upon reuniting of the Roman empire by Constantine the
Great, he looked for a place that could be truly a center for a new Roman Empire that
was centered on the Christian faith.  The reason that he chose the site of Byzantium was
two fold.  First, it was a logical link to the eastern parts of the empire and second it
would provide a formidable defense to any aggression from the Persians in the
east.

The transformation of the Roman empire into that of
the Byzantine empire was slow and did not have any real dividers in time.  The
"Byzantines" really considered themselves "Romans" and it was not until the divisions
that occurred between the papacy and the eastern orthodox church was there any
differentiation between the two.  Remember that the Ostrogothic and Visigothic conquests
within the western hemisphere of the empire made many changes in values, disciplines and
beliefs. The word "Byzantine" was not used until well in the 15th century to describe
the eastern part of the Roman empire.  However, there were many conflicts between the
eastern and western parts of the empire, mostly due to religious differences and
monetary jealousy.

The beginning of the "Byzantine Empire"
was of course with the establishment of Constantinople in 330.  Constantine the Great
wanted this city to be built from scratch as the center of the Christian world.  He and
his following emperors made Constantinople into one of the most elaborate and civilized
cities in the world.  The wealth that was displayed was incredible.  Until the Fourth
Crusade, Constantinople enjoyed 874 years of growth and stability.  Few cities in
history have lasted as long without being overrun by an invading
army.

The monetary history was probably the most important
aspect of the success of the empire.  Constantine the Great introduced several monetary
reforms with one of them being the creation of the gold Solidus at 72 to the Roman
pound.  This standard lasted throughout the history with only periodic debasement in
economically stressed parts of the empire or during periods of extremely weak
leadership. If anything can be learned from the Eastern Roman Empire is that monetary
stability and strength lead to strength within a civilization.