First attested in English in the early 15th century, initially in a range of senses encompassing '(public) policy; state; public order', the word police comes from Middle French police ('public order, administration, government'), in turn from Latin politia, which is the Latinisation of the Greek ???????? (politeia), "citizenship, administration, civil polity". This is derived from ????? (polis), "city".

Ancient policing

Law enforcement in ancient China was carried out by "prefects" for thousands of years since it developed in both the Chu and Jin kingdoms of the Spring and Autumn period. In Jin, dozens of prefects were spread across the state, each having limited authority and employment period. They were appointed by local magistrates, who reported to higher authorities such as governors, who in turn were appointed by the emperor, and they oversaw the civil administration of their "prefecture", or jurisdiction. Under each prefect were "subprefects" who helped collectively with law enforcement in the area. Some prefects were responsible for handling investigations, much like modern police detectives. Prefects could also be women. The concept of the "prefecture system" spread to other cultures such as Korea and Japan.

In ancient Greece, publicly owned slaves were used by magistrates as police. In Athens, a group of 300 Scythian slaves (the ?????????, "rod-bearers") was used to guard public meetings to keep order and for crowd control, and also assisted with dealing with criminals, handling prisoners, and making arrests. Other duties associated with modern policing, such as investigating crimes, were left to the citizens themselves.

In the Roman empire, the army, rather than a dedicated police organization, provided security. Local watchmen were hired by cities to provide some extra security. Magistrates such as procurators fiscal and quaestors investigated crimes. There was no concept of public prosecution, so victims of crime or their families had to organize and manage the prosecution themselves.

Under the reign of Augustus, when the capital had grown to almost one million inhabitants, 14 wards were created; the wards were protected by seven squads of 1,000 men called "vigiles", who acted as firemen and nightwatchmen. Their duties included apprehending thieves and robbers and capturing runaway slaves. The vigiles were supported by the Urban Cohorts who acted as a heavy-duty anti-riot force and even the Praetorian Guard if necessary.

Medieval policing

In medieval Spain, Santa Hermandades, or "holy brotherhoods", peacekeeping associations of armed individuals, were a characteristic of municipal life, especially in Castile. As medieval Spanish kings often could not offer adequate protection, protective municipal leagues began to emerge in the twelfth century against banditry and other rural criminals, and against the lawless nobility or to support one or another claimant to a crown.

These organizations were intended to be temporary, but became a long-standing fixture of Spain. The first recorded case of the formation of an hermandad occurred when the towns and the peasantry of the north united to police the pilgrim road to Santiago de Compostela in Galicia, and protect the pilgrims against robber knights.

Throughout the Middle Ages such alliances were frequently formed by combinations of towns to protect the roads connecting them, and were occasionally extended to political purposes. Among the most powerful was the league of North Castilian and Basque ports, the Hermandad de las marismas: Toledo, Talavera, and Villarreal.

As one of their first acts after end of the War of the Castilian Succession in 1479, Ferdinand II of Aragon and Isabella I of Castile established the centrally-organized and efficient Holy Brotherhood as a national police force. They adapted an existing brotherhood to the purpose of a general police acting under officials appointed by themselves, and endowed with great powers of summary jurisdiction even in capital cases. The original brotherhoods continued to serve as modest local police-units until their final suppression in 1835.

The Vehmic courts of Germany provided some policing in the absence of strong state institutions.

In France during the Middle Ages, there were two Great Officers of the Crown of France with police responsibilities: The Marshal of France and the Constable of France. The military policing responsibilities of the Marshal of France were delegated to the Marshal's provost, whose force was known as the Marshalcy because its authority ultimately derived from the Marshal. The marshalcy dates back to the Hundred Years' War, and some historians trace it back to the early 12th century. Another organisation, the Constabulary (French: Connétablie), was under the command of the Constable of France. The constabulary was regularised as a military body in 1337. Under Francis I of France (who reigned 1515–1547), the Maréchaussée was merged with the Constabulary. The resulting force was also known as the Maréchaussée, or, formally, the Constabulary and Marshalcy of France.

The English system of maintaining public order since the Norman conquest was a private system of tithings, led by a constable, which was based on a social obligation for the good conduct of the others; more common was that local lords and nobles were responsible for maintaining order in their lands, and often appointed a constable, sometimes unpaid, to enforce the law. There was also a system investigative "juries".

The Assize of Arms of 1252, which required the appointment of constables to summon men to arms, quell breaches of the peace, and to deliver offenders to the sheriffs or reeves, is cited as one of the earliest creation of the English police. The Statute of Winchester of 1285 is also cited as the primary legislation regulating the policing of the country between the Norman Conquest and the Metropolitan Police Act 1829.

From about 1500, private watchmen were funded by private individuals and organisations to carry out police functions. They were later nicknamed 'Charlies', probably after the reigning monarch King Charles II. Thief-takers were also rewarded for catching thieves and returning the stolen property.

The first use of the word police ("Polles") in English comes from the book "The Second Part of the Institutes of the Lawes of England" published in 1642.

Early modern policing

The first centrally organised police force was created by the government of King Louis XIV in 1667 to police the city of Paris, then the largest city in Europe. The royal edict, registered by the Parlement of Paris on March 15, 1667 created the office of lieutenant général de police ("lieutenant general of police"), who was to be the head of the new Paris police force, and defined the task of the police as "ensuring the peace and quiet of the public and of private individuals, purging the city of what may cause disturbances, procuring abundance, and having each and everyone live according to their station and their duties".

This office was first held by Gabriel Nicolas de la Reynie, who had 44 commissaires de police (police commissioners) under his authority. In 1709, these commissioners were assisted by inspecteurs de police (police inspectors). The city of Paris was divided into 16 districts policed by the commissaires, each assigned to a particular district and assisted by a growing bureaucracy. The scheme of the Paris police force was extended to the rest of France by a royal edict of October 1699, resulting in the creation of lieutenants general of police in all large French cities and towns.

After the French Revolution, Napoléon I reorganized the police in Paris and other cities with more than 5,000 inhabitants on February 17, 1800 as the Prefecture of Police. On March 12, 1829, a government decree created the first uniformed police in France, known as sergents de ville ("city sergeants"), which the Paris Prefecture of Police's website claims were the first uniformed policemen in the world.

In 1737, George II began paying some London and Middlesex watchmen with tax monies, beginning the shift to government control. In 1749 Henry Fielding began organizing a force of quasi-professional constables known as the Bow Street Runners. The Macdaniel affair added further impetus for a publicly salaried police force that did not depend on rewards. Nonetheless, In 1828, there were privately financed police units in no fewer than 45 parishes within a 10-mile radius of London.

The word "police" was borrowed from French into the English language in the 18th century, but for a long time it applied only to French and continental European police forces. The word, and the concept of police itself, were "disliked as a symbol of foreign oppression" (according to Britannica 1911). Before the 19th century, the first use of the word "police" recorded in government documents in the United Kingdom was the appointment of Commissioners of Police for Scotland in 1714 and the creation of the Marine Police in 1798.

In London

In 1797, Patrick Colquhoun was able to persuade the West Indies merchants who operated at the Pool of London on the River Thames, to establish a police force at the docks to prevent rampant theft that was causing annual estimated losses of £500,000 worth of cargo. The idea of a police, as it then existed in France, was considered as a potentially undesirable foreign import. In building the case for the police in the face of England's firm anti-police sentiment, Colquhoun framed the political rationale on economic indicators to show that a police dedicated to crime prevention was "perfectly congenial to the principle of the British constitution". Moreover, he went so far as to praise the French system, which had reached "the greatest degree of perfection" in his estimation.

With the initial investment of £4,200, the new trial force of the Thames River Police began with about 50 men charged with policing 33,000 workers in the river trades, of whom Colquhoun claimed 11,000 were known criminals and "on the game". The force was a success after its first year, and his men had "established their worth by saving £122,000 worth of cargo and by the rescuing of several lives". Word of this success spread quickly, and the government passed the Marine Police Bill on 28 July 1800, transforming it from a private to public police agency; now the oldest police force in the world. Colquhoun published a book on the experiment, The Co