The ancient Roman and Greek civilizations are seen as the most influential to modern day Western civilization. Because of this, it is easy to forget about other empires that existed during ancient history. Civilizations such as the Achaemenid Empire, Macedonian Empire and the Maurya Empire were all crucial during their times of existence.
The Achaemenid Empire existed from 550 - 330 BCE and was the largest empire the ancient world had ever seen. It extended from Anatolia and Egypt across western Asia to northern India 
and Central Asia¹. This was a Persian empire that is not widely known because most Western history textbooks simply remember the Persians as the civilization that went to war with Greece.
The Macedonian Empire was an ancient civilization in the northeast Greek peninsula. Macedonia began as a small kingdom, seemingly irrelevant to Classical Greek affairs to briefly acting as the most powerful
state in the world.
The Maurya Empire was an Iron Age power in ancient India, ruled by the Mauryan dynasty from 332 - 185 BCE. It consisted of much of modern day India and Pakistan. This was a brief empire but had a remarkable and famous emperor named Ashoka. After the Kalinga War of 260 BCE and the preceding years of bloodshed, Ashoka adopted Buddhism and the concept of dharma in his practices.
These are not the only lesser known ancient civilizations to have existed. Explore this section of BrainMass to discover others and broaden your knowledge of ancient history.
Reference:
1.The Achaemenid Persian Empire (550–330 B.C.). The Metropolitan Museum of Art. Retrieved from http://www.metmuseum.org/toah/hd/acha/hd_acha.htm
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