Like the speed light there isn’t really an inventor of the golden ratio. Its more like a fact of mathematics, which reveals itself in geometry. Many historical people like Pythagoras, Euclid, and Plato have been fascinated with this geometric ratio. More recently Kepler prove that the ratio is related to Fibonacci numbers. But the oldest proof of knowledge of this ratio is from an Indian text dated near 1200BC. Looks like those guys were smart even back then!