The Picts, of obscure origin, inhabited Scotland from prehistoric times. The Romans attempted vainly to penetrate Scotland, and their successive lines of forts and walls proved inadequate to contain the northern tribes of Picts and Celts. Although the Romans had little influence on Scottish life, Christianity had been introduced into Scotland before they left by St. Ninian and his disciples in the 5th cent. In the century and a half after the Roman evacuation (mid-5th cent.), four Scottish kingdoms came into being—that of the Picts in the north; that of the Scots who came from Ireland and founded Dalriada in what is now Argyll and Bute; that of the Britains in Strathclyde; and that of Northumbria (which also included northern England), founded by the Angles and settled largely by Germanic immigrants.

The mission of St. Columba (563) from Ireland reintroduced Christianity to Scotland. The usages of the Celtic Church differed in various details from those of Rome, introduced in the south of Britain by St. Augustine. Conflict between the two was settled in favor of Roman usage decided at the Synod of Whitby in 663, but Scottish Christianity only slowly adopted the Roman forms. After the decline of the Northumbrian power in Scotland began the raids of the Norsemen, who harried the country from the 8th to the 12th cent. In 794 they attacked the islands off Scotland and soon returned to live in the Hebrides; by 870 they were established in what came to be Caithness and Sutherland. In the mid-9th cent. Kenneth I established his rule over nearly all the land N of the Firth of Forth. His descendants pushed into Northumbria and by the 11th cent. ruled all of present Scotland except N Pictland and the islands.

Under Malcolm III, who married St. Margaret of Scotland (an English princess), there began a reorganization of the Scottish church and a gradual anglicization of the Lowland peoples. Malcolm invaded England after rejecting the claim of William II of England to sovereignty over Scotland, but peace followed the marriage of Malcolm's daughter to Henry I of England and allowed the process of feudalization in Scotland to continue. Although the clan system, based on blood relationships and personal loyalty to a chieftain, survived in the Highlands, feudal property laws were generally adopted in the Lowlands in the 11th and 12th cent. David I (1124-53) supported feudalism with land grants from the crown, encouraged the growth of self-governing burghs, and backed his bishops in their refusal to recognize the supremacy of the archbishop of York.

In the reign of William the Lion Scotland became a fief of England by a treaty extorted (1174) from William by Henry II. In 1189 Richard I sold the Scots their freedom, but he couched the agreement in ambiguous terms that allowed later English kings to revive the claim. The Norsemen were gradually pushed out of Scotland and finally defeated in 1263; only the Orkneys and Shetlands remained in Norse hands until the 15th cent. When Alexander III died in 1286, his heiress was the infant Margaret Maid of Norway; she was betrothed to the son of Edward I of England but died (1290) as a child. In the ensuing struggle among many claimants to the throne, Edward I declared for John de Baliol (1249-1315), who was crowned (1292), with Edward acknowledged as overlord of Scotland.

In Edward's war (late 13th cent.), with Philip IV of France, the Scots allied with Philip, thus beginning the long relationship with France that characterizes much of Scottish history. Edward won Scottish submission, but Scotland rose in revolt, first under Sir William Wallace, then under Robert the Bruce (later Robert I). Robert was crowned king at Scone in 1306, recaptured Scottish castles and raided across the English border, and finally defeated Edward II at Bannockburn in 1314. Edward III in 1328 signed a treaty acknowledging Scotland's independence, but during the troubled minority (1329-41) of David II he supported the pretender, Edward de Baliol, and invaded Scotland.

The reigns of David II and his successors (of the royal house of Stuart) were years of dissension and turbulence among the nobles and royal heirs and of repeated attacks from England. Social chaos was compounded by the scourge of the Black Death plague epidemic, which killed nearly a third of the population. In 1424 James I, who had spent his youth a prisoner at the English court, returned to Scotland. James vigorously attempted to revamp the laws and to establish control over his nobles. His murder in 1437 threw Scotland back into the old pattern of civil conflict during long royal minorities over the next century (see James II, James III, and James V). A brief respite of internal peace in this period of strife was provided by the reign of James IV, who perished with the flower of Scottish nobility at the battle of Flodden Field (1513).

James V perpetuated the French alliance by marrying Mary of Guise, who brought a large French contingent to Scotland with her. The Reformation came to Scotland primarily through the efforts of John Knox (1505-1572; see also Presbyterianism and Scotland, Church of). The religious issue was inextricably connected with opposition to the French Roman Catholic party of Mary of Guise (queen regent after James's death in 1542) and of her daughter Mary Queen of Scots, who lived in France as dauphine and then as queen.

By the time Mary Queen of Scots arrived (1561) in Scotland, Catholicism had almost disappeared from the Lowlands. The turbulent career of the young queen hinged primarily on her personal involvements and on the conflict between the crown and the nobility, now divided into pro-French (Catholic) and pro-English (Protestant) parties. Elizabeth I of England maintained the Protestant party with money and arms. Mary's struggle ended in her loss of the throne (1567), imprisonment in England, and execution (1587). Her son, James VI, broke away from his guardians in 1583 and accomplished the difficult task of subduing the nobility and establishing once and for all the supremacy of royal authority. In 1603, on Elizabeth's death, he succeeded to the English throne as James I of England. United under one crown, Scotland and England were finally at peace.

Scotland enjoyed comparative peace for a few years, as many of the nobility followed the court to England. Presbyterianism and its maintenance now became the great question. The desire to bar episcopacy (governance of the church by bishops), which was favored by the Stuarts, shaped every political move of the Scottish Parliament (Estates). The Covenanters declared their opposition to the liturgical forms imposed by Charles I and stoutly resisted his attempt to bring them to heel in the Bishops' Wars (1639-40). These wars led directly to the English civil war.

Although Scotland, like England, was somewhat divided in opinion, the great majority opposed the king, and Charles's efforts to win the Scots by yielding rights to Presbyterianism in 1641 came too late to sway the 8th earl of Argyll and his Covenanters. Yet James Graham, earl of Montrose, almost succeeded, with his wild Highlander troops, in winning Scotland for the king in 1644-45. Meanwhile, the Covenanters sought to force Presbyterianism on England, and the English Parliament proclaimed that form of religion in 1643. But the English army under Oliver Cromwell ultimately prevailed over Parliament, and the Scottish religion gained only toleration, not supremacy, in England.

Charles I surrendered to the Scots, who handed him over to the English Parliament. Scottish sympathies shifted to Charles, however, and their army fought for him in 1648. The execution of the king in 1649 caused a revulsion of feeling in Scotland, and the junction with England imposed by Cromwell (see Protectorate) was extremely unpopular. Many Scots rallied to Charles II, who was crowned at Scone in 1651, and the Restoration (1660) was cause for great rejoicing. The Stuarts, however, sought once more to restore episcopacy, and the Covenanters were, for many decades, subjected to severe persecution.

The Scots hated the Roman Catholic James II even more bitterly than the English did, and the accession in 1689 of William III and Mary II was met with widespread support, if not enthusiasm. With the Glorious Revolution (1688-89), Presbyterianism once more became the national church. But the Jacobites, supporters of the exiled Stuarts, caused great disruption, particularly in the Highlands, and the massacre of a Highland clan at Glencoe (1692) tended to discredit the new government. Scotland's commercial interests nursed economic grievances against William, primarily for his failure to support the Darién Scheme and for the discriminatory Navigation Acts.

Constitutional union of England and Scotland, which had been considered ever since the junction of the crowns, was rejected at this time by the English, but its desirability became increasingly apparent. The question of succession to the throne was a burning issue in the reign of Queen Anne (1702-14), whose children predeceased her, in face of assiduous Jacobite activity in both kingdoms. Finally, in order to assure the Hanoverian succession (provided in the Act of Settlement, 1701) after Anne's death, the union was voted by both Parliaments in 1707, providing for Scottish representatives in a Parliament of Great Britain. Equality of trading privileges and toleration of episcopacy, along with recognition of a Presbyterian Established Church of Scotland, were among the terms of the union. The Jacobites attempted in 1715 and again in 1745 to destroy the union, but without success, and Scotland had peace at last.

In the 18th cent. Scotsmen such as David Hume and Adam Smith stood in the forefront of the European Enlightenment. Educational standards, from elementary to university level, were high, and many English religious dissenters, barred from Oxford and Cambridge, received excellent educations in Scotland. From its intellectually vibrant atmosphere came many practical inventions to further the Industrial Revolution, including the work of James Watt. The economic results of the union eventually proved wholly favorable to Scotland, and the people gradually enjoyed a higher standard of living. Feudal land tenure slowly gave way to modern leases. Thriving commerce within the British Empire led to expansion of shipping and shipbuilding, and Glasgow achieved eminence as a commercial center.

The increasing market for meat and wool spurred new developments in agriculture and cattle breeding but unfortunately led also to the dispossession of a large part of the population in the Highland grazing lands during the inclosure actions of the later 18th and early 19th cent. The resultant emigration of Highlanders to Canada, the United States, and Australia nearly depopulated parts of Scotland. Early in the 18th cent. linen manufacture and, to a lesser extent, woolcloth manufacture, came to be of major importance in the Lowland towns. Toward the end of the 18th cent. cotton spinning and weaving on the new power machinery of the Industrial Revolution became Scotland's leading industries.

By the end of the 19th cent., metallurgical industry had come to dominate the economy; the exploitation of rich coal and iron fields resulted in a concentration of heavy industry in a central belt running from Ayrshire to Fife. The rise of a new middle class and an urban working class necessitated the same reform of corrupt and outmoded local institutions that occurred in England. Industrialization also produced severe social and economic distress, for which traditional private philanthropy proved inadequate, and led to outbreaks of unrest in city and countryside alike—such as the Crofters' War of hard-pressed tenant farmers in the 1880s. From Scotland emerged some of the first leaders of the British labor movement. Under Alexander MacDonald a powerful miners union developed in the 1860s. The first labor representatives in Parliament came from Scottish mining areas. James Keir Hardie, founder of the Independent Labour party, and James Ramsay MacDonald, first Labour prime minister, were Scotsmen.

Concentration on heavy industry meant that Scotland was an important arsenal in World War I. It also meant that Scotland suffered heavily in the depression between the wars. In World War II, despite the fact that its industry supplied a great deal of the British war material, Scotland was not extensively damaged by bombing. After the war the steady exodus of population from the Highlands continued; in an effort to make the Highlands again profitably habitable, a program of reforestation and hydroelectric development, begun in a small way as early as 1922, was increased. Immigration from Ireland added to Scotland's urban population. Many new diversified industries, especially high-tech industries, were started to relieve the strong emphasis on heavy industry that had unbalanced the Scottish economy. Efforts to attract tourists led to the construction of many modern hotels and the development of the Edinburgh festival of arts.

These improvements did not lessen a persistent nationalist movement that urged greater autonomy for Scotland. The movement became prominent with the discovery of North Sea oil in the 1970s and gained momentum in the 1980s when many Scots felt the government of Margaret Thatcher was unresponsive to them. When Tony Blair became prime minister in May, 1997, he made the devolution of authority one of the principal objectives of his government. In Sept., 1997, Scottish voters approved the establishment of a parliament to run their domestic affairs, with the power to make laws and set taxes. Elections were held and the body began sitting in 1999. The Labour party won the most seats, although not a majority, and established a coalition with the Liberal Democrats; the proindependence Scottish Nationalist party (SNP) became the principal opposition. The Labour-Liberal Democrat coalition remained in power after the 2003 elections, but the SNP won a plurality in 2007 and formed a minority government; it retained power with majority after the 2011 vote, and subsequently began development plans for a referendum on Scotland's status with respect to the United Kingdom. In 2012, the Scottish and British governments agreed to an independence referendum in late 2014. Alex Salmond, of the SNP, is the current Scottish first minister. See also Great Britain.