The usage of 'mil-réis as a word dates back to the economic crises of the 19th century, when the currency was devalued for the first time and most prices reached the thousands.
It was replaced in 1911 by the escudo in Portugal [one escudo (1$000)= one thousand réis] and in 1942 by the cruzeiro in Brazil. By the time it was replaced by cruzeiro in Brazil, one mil-réis (1$000) was worth a dozen loaves of bread.
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