The Royal Mail can trace its history back to 1516, when Henry VIII established a "Master of the Posts", a position that was renamed "Postmaster General" in 1710.

Upon his accession to the throne of England at the Union of the Crowns in 1603, James VI and I moved his court to London. One of his first acts from London was to establish the royal postal service between London and Edinburgh, in an attempt to retain control over the Scottish Privy Council.

The Royal Mail service was first made available to the public by Charles I on 31 July 1635, with postage being paid by the recipient. The monopoly was farmed out to Thomas Witherings.

In the 1640s Parliament removed the monopoly from Witherings and during the Civil War and First Commonwealth the parliamentary postal service was run at great profit for himself by Edmund Prideaux (a prominent parliamentarian and lawyer who rose to be attorney-general). To keep his monopoly in those troubled times Prideaux improved efficiency and used both legal impediments and illegal methods.

In 1653 Parliament set aside all previous grants for postal services, and contracts were let for the inland and foreign mails to John Manley. Manley was given a monopoly on the postal service, which was effectively enforced by Protector Oliver Cromwell's government, and thanks to the improvements necessitated by the war Manley ran a much improved Post Office service. In July 1655 the Post Office was put under the direct government control of John Thurloe, a Secretary of State, and best known to history as Cromwell's spymaster general. Previous English governments had tried to prevent conspirators communicating, Thurloe preferred to deliver their post having surreptitiously read it. As the Protectorate claimed to govern all of Great Britain and Ireland under one unified government, on 9 June 1657 the Second Protectorate Parliament (which included Scottish and Irish MPs) passed the "Act for settling the Postage in England, Scotland and Ireland" that created one monopoly Post Office for the whole territory of the Commonwealth. The first Postmaster General was appointed in 1661, and a seal was first fixed to the mail.

At the restoration of the monarchy, in 1660, all the ordinances and acts passed by parliaments during the Civil War and the Interregnum passed into oblivion, so the General Post Office (GPO) was officially established by Charles II in 1660.

Between 1719 and 1763, Ralph Allen, postmaster at Bath, signed a series of contracts with the post office to develop and expand Britain's postal network. He organised mail coaches which were provided by both Wilson & Company of London and Williams & Company of Bath. The early Royal Mail Coaches were similar to ordinary family coaches but with Post Office livery.

The first mail coach ran in 1784, operating between Bristol and London. Delivery staff received uniforms for the first time in 1793, and the Post Office Investigation Branch was established; it is the world's oldest recognised criminal investigations authority. The first mail train ran in 1830, on the Liverpool and Manchester Railway. The Post Office's money order system was introduced in 1838.

Uniform penny postage

In December 1839 the first substantial reform started when postage rates were revised by the short-lived Uniform Fourpenny Post. Greater changes took place when the Uniform Penny Post was introduced on 10 January 1840 whereby a single rate for delivery anywhere in Great Britain and Ireland was pre-paid by the sender. A few months later, to certify that postage had been paid on a letter, the sender could affix the first adhesive postage stamp, the Penny Black that was available for use from 6 May the same year. Other innovations were the introduction of pre-paid William Mulready designed postal stationery letter sheets and envelopes.

As Britain was the first country to issue prepaid postage stamps, British stamps are the only stamps that do not bear the name of the country of issue on them.

By the late 19th century, there were between six and twelve mail deliveries per day in London, permitting correspondents to exchange multiple letters within a single day.

The first trial of the London Pneumatic Despatch Company was made in 1863, sending mail by underground rail between postal depots. The Post Office began its telegraph service in 1870.

Pillar boxes

The first Post Office pillar box was erected in 1852 in Jersey. Pillar boxes were introduced in mainland Britain the following year. British pillar boxes traditionally carry the Latin initials of the reigning monarch at the time of their installation, for example: VR for Victoria Regina or GR for Georgius Rex. Such branding is not used in Scotland due to dispute over the current monarch's title. Some Scottish nationalists argue that Queen Elizabeth II should have simply been Queen Elizabeth as there had been no previous Queen Elizabeth of Scotland or of the United Kingdom of Great Britain and Northern Ireland (Elizabeth I was Queen only