Horse is one of the oldest symbols. And its visual symbolism starts with cave paintings what are 35000 years old. Horse importance to human civilization was huge for tens of thousands of years. First it was a pray. Later it was domesticated. And was the most important mans helper until industrial age. It was next to our ancestors through peace times and wars. And together with the dog a horse is the best friend of a man.
Horse was associated with sun and moon, water and fire. In indoeuropean culture horse was the one who was leading soles in underworld. A raider on a white horse going from east to west is a very common symbol in Europe. It is a sole racing from sunrise side to sundown side from the east side (kingdom of living) of the Nile to the west side of the Nile (Pyramids and kingdom of the dead). Horse appears in Egyptian, Greek, Roman, Chinese, Indian, Baltic, Catholic and other religions and mythologies.
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