Answer:
What was the most important reason for Alexander's ability to build such a large empire?
1.Alexander the Great's empire developed not only because of his military prowess but also because of his father's success, which took advantage of an unstable political context in Greece.
Alexander's background:
Alexander the Great, also known as Alexander III or Alexander of Macedonia, (born 356 BCE, Pella, Macedonia [northwest of Thessaloníki, Greece]—died June 13, 323 BCE, Babylon [near Al-Ḥillah, Iraq]), king of Macedonia (336–323 BCE), who overthrew the Persian empire, carried Macedonian arms to India, and laid the foundations for the Hellenistic world of territorial kingdoms. Already in his lifetime the subject of fabulous stories, he later became the hero of a full-scale legend bearing only the sketchiest resemblance to his historical career.
Alexander's early career:
Alexander received his earliest education under the tutelage of his relative, the stern Leonidas of Epirus. ... Alexander completed his education at Meiza in 340 B.C. A year later, while still just a teen, he became a soldier and embarked on his first military expedition, against the Thracian tribes.
Alexander built his empire by:
After three grueling years of warfare and three decisive battles, Alexander smashed the Persian armies at the Tigris River and conquered the mighty Persian Empire, including the legendary city of Babylon. ... While fighting the Persians, Alexander conquered Egypt and founded a city at the mouth of the Nile River.
Alexander kept his empire running by:
He led important campaigns and expanded his empire from Greece to Persia, Babylon, Egypt and beyond, taking advantage of local political contexts as he conquered new territory. ... Perhaps the greatest effect of his empire was the spread of Greek culture through the successor empires that long outlasted Alexander's rule.
Alexander's empire collapsed when:
Alexander's death was sudden and his empire disintegrated into a 40-year period of war and chaos in 321 BCE. The Hellenistic world eventually settled into four stable power blocks: the Ptolemaic Kingdom of Egypt, the Seleucid Empire in the east, the Kingdom of Pergamon in Asia Minor, and Macedon.
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