A passport is a document, issued by a national government, which certifies, for the purpose of international travel, the identity and nationality of its holder. The elements of identity are name, date of birth, sex, and place of birth. Most often, nationality and citizenship are congruent.

A passport does not of itself entitle the passport holder entry into another country, nor to consular protection while abroad or any other privileges, in the absence of any special agreements which cover the situation. It does, however, normally entitle the passport holder to return to the country which issued the passport. Rights to consular protection arise from international agreements, and the right to return arises from the laws of the issuing country. A passport does not represent the right or the place of residence of the passport holder in the country which issued the passport.

History

One of the earliest known reference to what served the major role of a passport is found in the Hebrew Bible. In , attributed to the time of the Persian Empire in about 450 BC, it is said that Nehemiah, an official serving King Artaxerxes I of Persia, asked leave to travel to Judea, and the king granted leave and gave him a letter "to the governors beyond the river" requesting safe passage for him as he traveled through their lands.

In the medieval Islamic Caliphate, a form of passport was used in the form of a bara'a, a receipt for taxes paid. Only citizens who paid their zakah (for Muslims) or jizya (for Dhimmis) taxes were permitted to travel to different regions of the Caliphate, thus the bara'a receipt was a "traveller's basic passport."

It is considered unlikely that the term "passport" is derived from sea ports, but rather from a medieval document required to pass through the gate ("porte") of a city wall.Fact: date=January 2009 In medieval Europe, such documents were issued to travelers by local authorities, and generally contained a list of towns and cities into which a document holder was permitted to pass. On the whole, documents were not required for travel to sea ports, which were considered open trading points, but documents were required to travel inland from sea ports.

King Henry V of England is credited with having invented what some consider the first true passport, notwithstanding the earlier examples cited, as a means of helping his subjects prove who they were in foreign lands.

Early passports included a description of the passport holder. Attachment of photographs to passports began in the early decades of the twentieth century, when photography became widespread.

In the later part of the nineteenth century and up to World War I, passports were not required, on the whole, for international travel in Europe, and crossing a border was easy. Consequently, comparatively few people had passports. The breakdown of the European passport system of the early part of the nineteenth century was a result of rail travel. Trains, used extensively from the mid-nineteenth century onward, traveled rapidly, carried numerous passengers, and crossed many borders. Those factors made enforcement of passport laws difficult. The general reaction was abolition of passport requirements. The Ottoman Empire and the Russian Empire maintained passport requirements for international travel, in addition to an internal-passport system to control travel within their borders.