Russia's first fiat currency, issued for the same reason as usual - government overspending on military affairs. Since there was not enough silver to back the ruble they invented the same solution every other country does: debase the currency.
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The term assignat is similar to the Russian word assignatsia which means "banknote". Assignatsionny rubl (assignation ruble) was used in Russia from 1769 until 1 January 1849. This had no connection to the French Revolution.
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