In the 1730s, all “U.S.” residents paid a 6-shilling tax for a “night watch” guard. Benjamin Franklin circulated an essay decrying “the inequity of this tax . . . since a poor widow housekeeper . . . paid as much as the wealthiest merchant, who had thousands of pounds’ worth of goods in his store.”
This led to a reform law. Ben's proportional tax resembles the U.S. federal income tax, enacted in 1913, with its progressive rate.
My, wasn't Ben busy!