* Hyperbole: It's an exaggerated statement, emphasizing the level of hunger.
* Historical context: In the past, horses were a valuable resource, and eating one would be a sign of extreme desperation.
* Folklore: There are various folklore tales about people being so hungry they'd eat anything, including horses.
It's important to note that:
* The phrase is not literal. No one actually intends to eat a horse!
* It's used humorously to emphasize the severity of hunger.
While the specific origin may be lost to time, the phrase's lasting use speaks to its effectiveness in conveying a strong feeling of hunger.