A Brief History of Mailboxes
Without the invention of the lowly mailboxes, civilization would have been very different. Good thing someone had the great idea to invent a sturdy receptable that would hold the world's most important and earliest form of communication -- the letter.
Before the 1850s, mailboxes were non-existent. They became necessary after the invention and widespread use of postage stamps, which allowed people more freedom in sending letters. With stamps, it was no longer necessary to purchase postage from the local post office.
Mailboxes become a must
Mailboxes became a necessity in 1863, when citizens began enjoying Free City Delivery. Letter carriers hand-delivered people's mails directly to their doorstep without any charge. Although the residential mailbox was already useful then, it wasn't until 1923 when it became mandatory for each household to have a mailbox or at least a letter slot. This ensured that people received their letters and letter carriers performed their jobs.
The right-sized mailbox
To ensure some form of uniformity when it came to the common mailbox, the U.S. Postal Service required that mailboxes for homes were big enough to make room for letter envelopes and magazines and be sturdy enough to withstand the weather and regular wear and tear. It should also have some sort of signaling device to alert someone that there is a letter inside the box for the recipient or that a package had arrived.
The most common type of mailbox used for residences is the tunnel style. It was designed in 1915 by an employee at the Post Office named Roy J. Joroleman, who was also an engineer. In some places, such as urban areas, mailboxes and letter slots were designed so they can be installed to the exterior of a home.
To make things more convenient for people, collection mailboxes began to be installed in the 1850s so people didn't have to go to the post office to send letters. At first they were installed on lampposts but these units were later replaced by free-standing mailboxes in 1894.