The messengers delivered their messages in person, each travelling on his own horse and taking time as needed for rest and refreshment (including stopping overnight if the length of journey required it).

[5] Under Edward IV, however, a more efficient system was put in place (albeit temporarily) to aid communications during his war with Scotland: a number of post houses were established at twenty-mile intervals along the Great North Road, between London and Berwick, to provide the king's messengers with fresh horses for each stage of the journey; in this way they were able to travel up to a hundred miles a day.

[5] The original meaning of the word 'post' (in the sense relevant to this article) comes from this idea of having horses placed or 'posted' (Latin positi) at regular intervals along a route for the swift conveyance of letters and messengers.

An executive ordinance of 1654 granted Members of Parliament (and certain other office-holders) a 'franking privilege', meaning that their letters would be conveyed free of charge (an arrangement, much taken advantage of over the years, which would remain in place until 1840).

[22] At first the new postal network was not especially well publicised;[21] but in his 1673 publication Britannia, Richard Blome sought to remedy this by describing in some detail the geographical disposition of the new 'general Post-Office', which he called an 'exceeding great conveniency' for the inhabitants of the nation.

Witherings had envisaged using 'foot-posts' for this purpose (in 1620 Justices of the Peace had been ordered to arrange appointment of two to three foot-posts in every parish for the conveyance of letters),[24] though in practice precise details were often left to the local postmaster.

'Packet boats', offering a regular scheduled mail service, were already in use for the passage between Holyhead and Dublin; but for letters to and from the Continent the post was entrusted to messengers, who would make their own travel arrangements.

Often a messenger with a locked satchel would be employed by the postmaster to deliver and receive items of mail around town; he would alert people to his presence by ringing a hand bell.

After initial resistance from the postal authorities, a trial took place in 1784, by which it was demonstrated that a mail coach departing from Bristol at 4pm would regularly arrive in London at 9 o'clock the following morning: a day and a half quicker than the post horses.

The development of a national rail network, quickly embraced by the Post Office, coincided with the ground-breaking introduction of uniform penny postage (qv below) and to a significant extent it made possible the dynamic growth of the UK postal service that followed.

[5] Hill's proposals, published in a 100-page pamphlet in 1837, were strongly repudiated by the Post Office under its long-standing Secretary Sir Francis Freeling and by the Postmaster General Lord Lichfield, who described them in the House of Lords as being 'of all the wild and visionary schemes [...] the most extraordinary';[35] but among the general public, by contrast, Post Office reform became something of a cause célèbre, with petitions and public meetings attracting large levels of support.

Few other organisations, either of state or of commerce, could rival the early Victorian Post Office in the extent of its national coverage, and its counters began to be relied upon for providing other government services (e.g. the issuing of licences of various types).

Henry Fawcett in the 1880s greatly expanded its operations and encouraged the use of savings stamps; by the end of the century the number of POSB branches had increased to 14,000, making it the largest banking system in the country.

[46] When new forms of communication came into existence in the 19th and early 20th centuries the GPO claimed monopoly rights on the basis that like the postal service they involved delivery from a sender and to a receiver.

[49] The fledgling department was overseen by Frank Scudamore (who had devised and carried out the plan for nationalisation), but he resigned in 1875 after he was found to have diverted money from the Savings Bank and elsewhere in a vain attempt to mitigate the fast-rising costs of the expanding operation.

[58] The GPO ran the nation's telegraph and telephone systems, as well as handling some 5.9 billion items of mail each year, while branch post offices offered an increasing number of financial, municipal and other public services alongside those relating to postage.

The government put pressure on the Post Office (and other employers) to provide jobs for returning ex-servicemen; most of the temporary staff engaged during the war (including the pioneering wartime postwomen and telegraph girls) were dismissed.

In 1920 the basic rate was again raised, to 2d, in an attempt to cover the GPO's rising wage bill and the cost of the telegraph and telephone businesses, which were running at a deficit; but two years later it was again reduced to 1½d (at which level it remained until 1940).

[73] Among other things he established the influential GPO Film Unit, while his acumen in the field of graphic design led to the Post Office becoming a leader and trend setter in its use of posters for the purposes of marketing, information and publicity.

Whilst immediately successful, it proved costly both to Imperial Airways (who had drastically underestimated the volume of cargo it would have to carry)[notes 15] and the Post Office (who had agreed to subsidise the company through tonnage payments).

[76] During World War II the generation of engineers trained by the GPO for its telecommunications operations were to have important roles in the British development of radar and in code breaking.

The Colossus computers used by Bletchley Park were designed and built by GPO engineer Tommy Flowers and his team at the Post Office Research Station in Dollis Hill.

[81] Tony Benn arrived as Postmaster General in October 1964, and promptly abolished the traditional red coats and top hats of the Post Office Headquarters doormen.

By December he was persuaded of the need to change the status of the Post Office from government department to public corporation (a proposition which was broadly supported by senior officials, but opposed by the unions).

Having outgrown its premises in Lombard Street, the General Post Office purchased slums on the east side of St. Martin's Le Grand and cleared them to establish a new headquarters, Britain's first purpose-built mail facility.

[88] In 1874, a new headquarters building ('GPO West') was opened on the western side of the street, containing a suite of public rooms and offices for the Postmaster General, the senior officials and all their administrative staff.

[90] In the early 18th century the authority of Ministers of the Crown to open and read letters for reasons of public safety had been clearly established by statute, drawn up by Lord Somers.

[20] In 1910, however, the Home Secretary (Winston Churchill) issued a 'general warrant' allowing the Secret Service Bureau to intercept letters at will; in the run-up to the First World War individuals who had been placed under surveillance routinely had their mail monitored.

During the Second World War, and for some years after, a department called the GPO Special Investigations Unit was responsible for intercepting letters as part of British intelligence service operations.

He departed in September 1968, after which it was announced that the Postmaster General, John Stonehouse, would assume the role of 'Chairman and Chief Executive' in preparation for the business's re-establishment as a public corporation the following year.