The large horn represents Alexander the Great, the mighty first king who established the Greek Empire. Two centuries after Daniel, Alexander quickly conquered the world (Daniel 8:5). He defeated Persia in 331 BC. Alexander died in 323 BC when he was 33 years old. But not before he allowed people to call him a god.
Josephus records that some Jewish priests showed the book of Daniel to Alexander. However, Alexander treated Homer’s Iliad as his sacred book and relied on it for guidance.