Polity in the context of "British Islands"

A country is an area of land, which has its own government and laws, or used to have them, such as a state, a nation, a nation state, or other political entity. When referring to a specific polity, the term "country" may refer to a sovereign state, a state with limited recognition, a constituent country, or a dependent territory. Most sovereign states, but not all countries, are members of the United Nations.

There is no universal agreement on the number of "countries" in the world with a range between 193 to 237. This ambiguity is a result of several states having disputed sovereignty status or limited recognition, and a number of non-sovereign entities are commonly considered countries. The definition and usage of the word "country" has fluctuated and changed over time. The Economist wrote in 2010 that "any attempt to find a clear definition of a country soon runs into a thicket of exceptions and anomalies."

A constitution, or supreme law, is the aggregate of fundamental principles or established precedents that constitute the legal basis of a polity, organization or other type of entity, and commonly determines how that entity is to be governed.

When these principles are written down into a single document or set of legal documents, those documents may be said to embody a written constitution; if they are encompassed in a single comprehensive document, it is said to embody a codified constitution. The constitution of the United Kingdom is a notable example of an uncodified constitution; it is instead written in numerous fundamental acts of a legislature, court cases, and treaties.

Jurisdiction (from Latin juris 'law' and dictio 'speech' or 'declaration') is the legal term for the legal authority held by a legal entity to enact justice. Jurisdiction is rarely claimed to be complete: rather it is limited for example by geography, subject matter, or other factor. It is only within the scope (inside the limits) of such jurisdiction that, for example, the parties to a dispute have standing to bring the matter (a legal question) before a judge, who has power (or 'jurisdiction') to decide it authoritatively.

A "jurisdiction" can also be understood as a category name for any separate polity legally constituted as such — for any government with legislative and other legal power over a particular territory, whether that area is a nation state or some smaller region. Thus, Australia, Arizona, North Yorkshire and New York City are each "a jurisdiction". In federations like the United States, jurisdiction in this polity sense applies at multiple levels (e.g., local, state, and national/federal).

Mainland is defined as "relating to or forming the main part of a country or continent, not including the islands around it [regardless of status under territorial jurisdiction by an entity]." The term is often politically, economically and/or demographically more significant than politically associated remote territories, such as exclaves or oceanic islands situated outside the continental shelf.

In geography, "mainland" can denote the continental part of any polity or the main island within an island nation. In geopolitics, "mainland" is sometimes used interchangeably with terms like metropole as an antonym to overseas territories. In the sense of "heartland", mainland is the opposite of periphery. In some language a separate concept of "mainland" is missing and is replaced with a "continental portion".

A political union is a type of political entity which is composed of, or created from, smaller polities or the process which achieves this. These smaller polities are usually called federated states and federal territories in a federal government; they are called prefectures, regions, or provinces in the case of a centralised government. This form of government may be created through voluntary and mutual cession and is described as unionism by its constituent members and proponents. In other cases, it may arise from political unification, characterised by coercion and conquest. The unification of separate states which, in the past, had together constituted a single entity is known as reunification. Unlike a personal union or real union, the individual constituent entities may have devolution of powers but are subordinate to a central government or coordinated in some sort of organization. In a federalised system, the constituent entities usually have internal autonomy, for example in the setup of police departments, and share power with the federal government, for whom external sovereignty, military forces, and foreign affairs are usually reserved. The union is recognised internationally as a single political entity. A political union may also be called a legislative union or state union.A union may be effected in many forms, broadly categorized as:

• Incorporating union
• Incorporating annexation
• Federal union
• Federative annexation
• Mixed unions

Sovereignty can generally be defined as supreme, independent control and lawmaking authority over a territory. It finds expression in the power to rule and make law. Sovereignty entails hierarchy within a state as well as external autonomy for states. In any state, sovereignty is assigned to the person, body or institution that has the ultimate authority over other people and to change existing laws. In political theory, sovereignty is a substantive term designating supreme legitimate authority over some polity. Under international law, sovereign states are all considered equal, and no state can interfere with the internal affairs of another sovereign state. While Article 2(7) of the UN Charter explicitly recognizes the sovereignty of states, and in general there is a principle of non-interference in the domestic affairs of sovereign states, the UN Security Council’s Chapter VII powers clearly contemplate the use of force against a state when necessary to restore peace. Further, the recent Responsibility to Protect (R2P) authorizes the United Nations to take action to “avert a humanitarian catastrophe” within a state when that state’s government cannot or will not act.

A state is generally considered to have sovereignty over a territory when it has consistently exercised state authority there without objection from other states. De jure sovereignty refers to the legal right to do so; de facto sovereignty refers to the factual ability to do so. This can become an issue of special concern upon the failure of the usual expectation that de jure and de facto sovereignty exist at the place and time of concern, and reside within the same organization.

The Ptolemaic Kingdom (/ˌtɒlɪˈmeɪ.ɪk/; Koine Greek: Πτολεμαϊκὴ βασιλεία, Ptolemaïkḕ basileía) or Ptolemaic Empire was an ancient Greek polity based in Egypt during the Hellenistic period. It was founded in 305 BC by the Macedonian Greek general Ptolemy I Soter, a companion of Alexander the Great, and ruled by the Ptolemaic dynasty until the death of Cleopatra VII in 30 BC. Reigning for nearly three centuries, the Ptolemies were the longest and final dynasty of ancient Egypt, heralding a distinct era of religious and cultural syncretism between Greek and Egyptian culture.

Alexander the Great conquered Egypt in 332 BC during his campaigns against the Achaemenid Empire. Alexander's death in 323 BC was followed by the rapid unraveling of the Macedonian Empire amid competing claims by the diadochi, his closest friends and companions. Ptolemy, one of Alexander's most trusted generals and confidants, won control of Egypt from his rivals and declared himself its ruler in 305 BC. Alexandria, a Greek polis founded by Alexander, became the capital city and a major center of Greek culture, learning, and trade for the next several centuries. Following the Syrian Wars with the Seleucid Empire, a rival Hellenistic state, the Ptolemaic Kingdom expanded its territory to include eastern Libya, the Sinai, and northern Nubia.

The fall of the Western Roman Empire, also called the fall of the Roman Empire or the fall of Rome, was the loss of central political control in the Western Roman Empire, a process in which the Empire failed to enforce its rule, and its vast territory was divided among several successor polities. The Roman Empire lost the strengths that had allowed it to exercise effective control over its Western provinces; modern historians posit factors including the effectiveness and numbers of the army, the health and numbers of the Roman population, the strength of the economy, the competence of the emperors, the internal struggles for power, the religious changes of the period, and the efficiency of the civil administration. Increasing pressure from invading peoples outside Roman culture also contributed greatly to the collapse. Climatic changes and both endemic and epidemic disease drove many of these immediate factors. The reasons for the collapse are major subjects of the historiography of the ancient world and they inform much modern discourse on state failure.

In 376, a large migration of Goths and other non-Roman people, fleeing from the Huns, entered the Empire. Roman forces were unable to exterminate, expel or subjugate them (as was their normal practice). In 395, after winning two destructive civil wars, Theodosius I died. He left a collapsing field army, and the Empire divided between the warring ministers of his two incapable sons. Goths and other non-Romans became a force that could challenge either part of the Empire. Further barbarian groups crossed the Rhine and other frontiers. The armed forces of the Western Empire became few and ineffective, and despite brief recoveries under able leaders, central rule was never again effectively consolidated.

In modern historiography, the Western Roman Empire were the Roman Empire's western provinces, collectively, during any period in which they were administered separately from the eastern provinces by a separate, independent imperial court. Particularly during the period from AD 395 to 476, there were separate, coequal courts dividing the governance of the empire into the Western provinces and the Eastern provinces with a distinct imperial succession in the separate courts. The terms Western Roman Empire and Eastern Roman Empire were coined in modern times to describe political entities that were de facto independent; contemporary Romans did not consider the Empire to have been split into two empires but viewed it as a single polity governed by two imperial courts for administrative expediency. The Western Empire collapsed in 476, and the Western imperial court in Ravenna disappeared by 554, at the end of Justinian's Gothic War.

Though there were periods with more than one emperor ruling jointly before, the view that it was impossible for a single emperor to govern the entire Empire was institutionalized by emperor Diocletian following the disastrous civil wars and disintegrations of the Crisis of the Third Century. He introduced the system of the Tetrarchy in 286, with two senior emperors titled Augustus, one in the East and one in the West, each with an appointed subordinate and heir titled Caesar. Though the tetrarchic system would collapse in a matter of years, the East–West administrative division would endure in one form or another over the coming centuries. As such, the unofficial Western Roman Empire would exist intermittently in several periods between the 3rd and 5th centuries. Some emperors, such as Constantine I and Theodosius I, governed, if briefly, as the sole Augustus across the Roman Empire. On the death of Theodosius in 395, the empire was divided between his two infant sons, with Honorius as his successor in the West governing briefly from Mediolanum then from Ravenna, and Arcadius as his successor in the East governing from Constantinople.

Self-governance, self-government, self-sovereignty or self-rule is the ability of a person or group to exercise all necessary functions of regulation without intervention from an external authority. It may refer to personal conduct or to any form of institution, such as family units, social groups, affinity groups, legal bodies, industry bodies, religions, and political entities of various degrees. Self-governance is closely related to various philosophical and socio-political concepts such as autonomy, independence, self-control, self-discipline, and sovereignty.

In the context of nation states, self-governance is called national sovereignty which is an important concept in international law. In the context of administrative division, a self-governing territory is called an autonomous region. Self-governance is also associated with political contexts in which a population or demographic becomes independent from colonial rule, absolute government, absolute monarchy, or any government that they perceive does not adequately represent them. It is therefore a fundamental tenet of many democracies, republics and nationalist governments. Mahatma Gandhi's term "swaraj" is a branch of this self-rule ideology. Henry David Thoreau was a major proponent of self-rule in lieu of immoral governments.