Rppc postcard dating
Before postcards, some people sent cards through the mail with attached postage.
Because of the absence of message space on the address side of postcards, the Post Card Period is also known as the Undivided Back Period.
Congress passed legislation on June 8, 1872, that approved government production of postal cards.
The first government-produced postcard was issued on May 1, 1873.
The dates for each time period are not concrete and different sources contain slightly variable dates.
It is also important to keep in mind that postcard types produced in one period could also be produced in another, but were simply not produced in the same volume as other card types of the period.