Ireland has a long history which has always been inter-connected with it's closest neighbour, Great Britain. Sadly, much of Ireland's history has been marked by conflict and bloodshed, but the Queen's visit in 2011 - the first by a British monarch to the Irish republic since independence in 1921 - was widely viewed as a symbol of a new, peaceful Ireland.
Arrival of Christianity
Christianity arrived in Ireland before the 5th century, probably via immigrants from the Roman Empire. Ireland already had a bishop, Palladius, when St Patrick arrived, but Patrick helped spread the new religion by converting several important kings and cheftains. Today, you can visit one early Christian site, dating from the 7th century, at Skellig Michael, off the southwest coast of Ireland. The rocky island is a UNESCO World Heritage site and you can view the small "beehive" huts where the early monks worked and worshipped.
Anglo-Normans arrived from Great Britain in the 1160s fleeing wars in Wales. The English monarch, King Henry II, followed them and in 1171 the Irish high kings pledged allegiance to Henry. Henry and the Norman barons quickly established a colony on the east coast based around Dublin before expanding it to include strongholds in the northeast (Ulster) and the southwest (Munster). They built formidable castles, several of which - for example at Carrickfergus and Limerick - you can visit today. The Anglo-Norman invasion changed Irish society forever.
The Plantation was a true turning point in Irish history because it introduced large numbers of Protestants to the island for the first time. King James I approved the idea to consolidate his control and exploit Ireland's natural resources. A mix of private investment and venture capital funded the plantation and established important urban centres like Belfast, Londonderry/Derry and Coleraine. By 1641, 22,000 English people had settled in Munster and a further 15,000 Scots in Ulster. The dispossessed native Irish resented the new inhabitants and rebelled in 1641, killing an estimated 12,000 Protestant settlers.
The Williamite wars were a wider conflict for the English throne between Catholic King James II and Protestant King William III, but its decisive battles were fought in Ireland and its effects left a long legacy in the island. Having fled England, James arrived in Ireland in 1689 but his army was defeated by Protestant supporters of William at Enniskillen, while the walled city of Derry resisted a Jacobite siege later that year. In 1690, William decisively defeated James at the Battle of the Boyne, securing the British crown for himself and the Protestant ascendancy in Ireland.
Act of Union
The 1800 Act of Union brought Ireland into the United Kingdom for the first time. Previously, Ireland had been governed by a parliament in Dublin but had been very unsettled; a rebellion had taken place in 1798. Unionist politicians hoped that Union would reduce the likelihood of another rebellion but it was not to be: the Act did not recognise the Catholic faith and became a focus of resentment for the nationalist movement that emerged in the 19th century.
The Famine in the late 1840s marked the country for decades afterwards. The population declined by one-fifth between 1845 and 1851; around a million people died in Ireland and thousands more emigrated - often to North America - to escape the suffering. Many poor families were totally reliant on the potato to survive, so the appearance of a fungal infection in 1845, and its recurrence in 1846 and 1848 left them starving and vulnerable to other diseases like scurvy and typhus.
Home Rule crisis
Unionist vied with Nationalist in the Home Rule Crisis or 1912-14. Nationalists wanted to restore an Irish Parliament in Dublin, while Unionists wanted to maintain Ireland's position within the United Kingdom. Over 470,000 Unionists signed a pledge in September 1912 to resist Home Rule and the following year Unionist leaders bought guns to arm this resistance movement. Nationalist leaders quickly followed, and by mid-1914, 90,000 Ulster Volunteers and 160,000 Irish Volunteers were being trained for combat. However, the start of World War I prevented conflict breaking out between the two groups. (See references 1 and 8)
The 1916 Easter Rising pushed Irish republican, rather than more moderate nationalist, ideals to the forefront and ultimately led to the formation of the Irish Republic. A small group of republicans occupied important buildings in Dublin over the Easter weekend in 1916 and fought a short battle with British soldiers before surrendering. In all, 450 people died, including 254 civilians. Initially, most Irish people resented the rebellion, but the execution of its leaders changed public opinion and helped revitalise the republican cause.