READ THE DESCRIPTION BELOW:
First of all, the video is a little old. There are two european empires missing:
The SWEDISH EMPIRE and the DUTCH EMPIRE.
Secondly: There is no "Polish empire". There is Polish-Lithuanian Commonwealth, which is a federation, not a centralised empire ruled by a sole monarch or emperor.
AND LAST, BUT NOT LEAST: Bulgaria and Armenia were empires. Bulgaria becomes an empire during the reign of tsar Simeon the Great (893-927), who extends its territories to more than 750 000 km2 and gains the title "tsar" (emperor) from the Byzantine empire. It was also an empire during the reign of tsar (emperor) Kaloyan, Ivan Asen II and more...
Armenia was an empire during the reign of Tigranes the Great (95-55 BC) who defeats the parthians and the seleucids extends the armenian territory to about 400 000 km2 and is known as "king of the kings" even among the romans.
...and YES, the so called "Macedonian empire" has nothing to do with today's state of FYROM. "Macedonia" is the name of an antique kingdom where the official language was the ancient greek. Also, Alexander the Great spreaded the greek culture through the Middle east.
