The second style of beer created by men and women. Once the spontaneous fermentation was understood, people harvested yeast from the first batch and used it in the next batch. Since the supply of the other ingredients, the malts and the spices, was not very consistent, every batch ended up with another color. Not too pale and not too dark, thus amber. Since people drank beer out of wooden, stone or iron cans the color of the beer didn’t really matter, nobody was really able to see the color.
Amber ales are average in alcohol content. Today they are around 5% by volume, but in the past they were around 2%.