1650-1793
During the War of the Spanish Succession a British fleet under Sir George Rooke attacked Gibraltar on 21 July 1704 and the fortress fell on 24 July. It was besieged almost immediately by Spanish and French forces, who were unsuccessful, losing some 10,000 men compared to 400 British. Ceded to Britain in 1713 under the Treaty of Utrecht. The Spaniards were not happy with this result and made assaults in 1720 and 1727. Neither were successful.

In 1779 Spaniards and French began a further assault and this developed into one of the most famous sieges in history. Starting on 16 July 1779, it lasted until 5 February 1783. Throughout, British forces held firm and finally the blockade was withdrawn. Although letters from the garrison exist, no official postal service was introduced until the early part of the 19th century.

1793-1815
For the first time in many wars to come, Gibraltar was an important naval base for Britain. Used by the Royal Navy to maintain their southern blockade of France and their command of the Mediterranean after the Battle of the Nile in 1798.

In the early years of the century the P0 established in Gibraltar was a branch of the GPO in London. By Act of Parliament of 2 December 1806 the Postmaster-General was authorized to operate a packet to Gibraltar and Malta from Falmouth. Handstruck markings were introduced at this time and are known from 1809.

1815-50
Gibraltar continued to use handstruck markings even after stamps were issued in Britain. In August 1835 the GPO packet was withdrawn and replaced by a contract service operated by the Peninsula line. This operated from Falmouth until 1862. Stops were also made at Vigo, Malaga and Cadiz as well as Lisbon and Oporto. In February 1843 the Great Liverpool left Southampton with the first passengers for the Far East. This service became monthly and later, in 1853, twice monthly.

P & 0 shipping line continued use Gibraltar as a port of call for transfer of mail and it was also used for Spanish mail which was transferred the Spanish P0 at San Roque.

By convention with Spain it was agreed that mail between Spain and Gibraltar should be regarded as local post. As a result the British internal ½d postcard was placed on sale and can be found used to Spain.

Overprinted stamps were in new colours and were replaced by Gibraltar's own adhesives in December 1886.

In 1857 the first British P0 in Morocco had been opened in Tangier. No stamps were provided but mail was passed to Gibraltar and cancelled. On the transfer of the Gibraltar P0 from London to the Colonial Office in 1886 control of the Tangier P0 was also transferred and Gibraltar stamps were placed on sale there and in other ports where consular offices continued to act as PAs. Stamps of Gibraltar continued to be used in Morocco until 1898, when stamps overprinted 'Morocco Agencies' were placed on sale. These in turn were replaced in 1907, when the British GPO resumed control of the PAs in Morocco.

Gibraltar joined the UPU in 1876.

1914-18
During World War I Gibraltar acted as a naval base for the Allied Mediterranean fleets. The garrison was enlarged and the volume of mail from the forces increased.

1939-45
Major naval supply base throughout World War II and particularly during the siege of Malta. Field POs operated within the 'colony and were used to cancel Gibraltar stamps. Owing to problems of perforating supplies of stamps when the printers were damaged by bombs in 1941-2, a number of unusual compound perforations appear on Gibraltar stamps. Some of these are rare.

1945 to date
A new constitution was granted in 1950 and revisions occurred in 1964 and 1969. However, Gibraltar remained a British possession and a referendum in 1969 showed that Gibraltarians were almost 100 per cent against any link with Spain. In 1969 Spain closed the frontier which was not re-opened until February 1985.