How it all looked in the past…

Before 1066, England, Wales, Scotland and Ireland were all separate states ruled by different kings. England conquered Wales in 1277 and the two countries legally joined together in 1536. In 1603, Scotland and England were united under one ruler ‒ James VI of Scotland became James I of England. The two countries kept their own parliaments. They were joined politically in 1707.

Ireland was added in 1800 to create the United Kingdom of Great Britain and Ireland. The 26 counties of the Irish Republic broke free in 1921. In 1997, Scotland and Wales gained a degree of self-government - called devolution. Even Northern Ireland – where some unionists were so determined to stay within the United Kingdom that they fought to do so – began a rolling process towards devolution after 1998.

The Early Modern Age

Under the rule of the Tudors and the Stuarts, the shape of the United Kingdom changed quite a bit.

Wales

Members of the Tudor family had supported Owain Glyndŵr (who started a rebellion in Wales), but over a century later the Tudor king, Henry VIII, annexed Wales to England.

In 1536 and 1543, Henry VIII passed the Laws in Wales Acts - often called the 'Acts of Union'. These imposed the English language, English law and administration on all of Wales.

The stated aim of the 1536 act was utterly to wipe out Welsh customs. The Welsh language began to die out, but Welsh scholars tried to preserve it and:

 in 1588 William Morgan translated the Bible into Welsh  the Cymmrodorion Society, meaning 'Earliest Natives' Society, was founded by London Welshmen in 1751 to collect and preserve Welsh literature and records

Scotland

Scotland and England were united under one ruler when James VI of Scotland became King James I of England in 1603, but Scotland remained an independent country.

Things got worse after the English expelled James II in 1688:

 Many Highlanders were Catholics, and the rule of new English King, William III, had to be imposed by force, sometimes using other Scots eg the 'Glencoe Massacre' of 1692.  The Scots were also angered when the English failed to support a Scottish colony in Darién, in Central America in 1698.

 The English were afraid that the Scots would choose to go back to the Stuarts and renew the 'auld alliance' with France.  It took five years of tricky negotiation, bullying and bribery to get the Scottish Parliament to agree to the 1706 Treaty of Union. Some welcomed the idea of the union, but many were unhappy.  The two parliaments and two royal titles were combined.  Scotland was able to keep its own legal system, education system and the Church of Scotland.  As a result of the Acts of Union (1707), Scotland and England, and also Wales, together formed 'the United Kingdom of Great Britain'.  Some Scots hated the Union. This led to the 1715 and 1745 Jacobite rebellions, both of which failed.  After the 1745 rebellion, the use of the Gaelic language by Highlanders was banned, and they weren't allowed to wear tartan or play bagpipes.

Ireland

In 1541, Henry VIII declared himself King of Ireland. The Tudors confiscated land, the 'Plantations', from Irish Catholics and gave it to Scottish and English settlers.

The Irish often rebelled, and at the start of the English Civil War they attacked and killed many of the settlers (1641). The English put down these uprisings – when Oliver Cromwell captured Drogheda and Wexford (1649), his men slaughtered the defenders.

During the Glorious Revolution of 1688‒1689, the Irish again went to war against the English, in support of James II against William III.

 They were defeated at the Battle of the Boyne, 12 July 1690.  The English government then passed 'penal laws' which prevented Catholics from worshipping, taking part in their own government, or owning a horse or a gun.