The modern definition of UBI stipulates the grant must be in cash, and because small-scale hunter-gatherer or agrarian communities do not have cash economies, they do not have UBIs. But these practices show how the values that motivate much of the modern UBI movement are not new to politics but have been recognized and practiced for a very long time.
Some writers trace the beginning of UBI history to ancient Athens, which used revenue from a city-owned mine to support a small cash income for Athenian citizens. This institution sounds like a UBI, except that the meaning of citizen was very different in ancient Athens. Citizens were a small, elite portion of the population. Noncitizens, such as slaves, women, and free noncitizen males, were the bulk of the population and virtually all of its labor force. A UBI for the elite is no UBI at all.
Proposals that begin to fit the modern definition of UBI begin in the 1790s with two writers, Thomas Paine and Thomas Spence. Paine’s famous pamphlet “Agrarian Justice” argued that because private ownership of the land had deprived people of the right to hunt, gather, fish, or farm on their own accord, they were owed compensation out of taxes on land rents. He suggested this compensation should be paid in the form of a large cash grant at maturity plus a regular cash pension at retirement age. That amounts to a stakeholder grant plus a citizens pension: nearly, but not quite, a UBI.
From a similar starting point, Spence carried the argument through to a full UBI, calling for higher taxes on land and a regular, unconditional cash income for everyone. If anyone can be said to be the “inventor” of UBI, it is Thomas Spence, but his proposal remained obscure, and the idea had to be reinvented many times before it became widely known.