Attempts to help balance postal budgets produced many advertising ideas over the years since the first postage stamps were issued. The Great Britain Mulready envelope which was issued coincidentally with the Penny Black in 1840 was the first to bear advertising. In this case, it was privately done but the advertisers sold the envelopes to users for less than face value to encourage their use.
New Zealand experimented with what is called backprint advertising which was printed on the backs of some late nineteenth century stamps and then sold by the advertisers below face value to encourage use. But government-sponsored advertising began first in Europe in the early part of the nineteenth century.
Many countries, including France, Germany, and Denmark sold advertisements in the labels of the booklets and booklet panes that were produced at the time. Italy did one better, placing ads on labels that were an intrinsic part of the stamp and were meant to be used on the letter as part of the postage stamp. Italy issued nineteen of these and many are great rarities and are often worth more used than mint. Finding them on the cover is very difficult.
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