It has continued up until present day but persecution has decreased extremely over the past 300 years. Were any specific groups targeted? Yes, Catholic Irish were strongly persecuted by English Protestants, which continues into present day. North Ireland seceded but was subject to much violence and was eventually forced back under British control, and still is the center of most of the heated debates of today. How were they persecuted? Irish people were discriminated against and even murdered by English people.
One of the most infamous acts came in 1972, when British paratroopers opened fire on a group of Catholic demonstrators and killed 14 people. The Penal Laws were considered to be the first form of official apartheid issued in the world, dividing and targeting people by their religion. All those not of the Anglican/Lutheran faith including not only Catholics but also Jews, Presbyterians and other types of Protestants were denied rights in relation to property ownership, political participation, and university education.
Prohibition on mixed marriages on the basis of religious and racial grounds led to many rallies and riots by the Irish against the discrimination and prejudice they faced. How does this affect people today? Ethnic relations in the Republic of Ireland are relatively peaceful, given the uniformity of national culture, but Irish Travellers have often been the victims of prejudice. In Northern Ireland the level of ethnic conflict, which is inextricably linked to the provinces divergence of religion, nationalism, and ethnic identity, is high, and has been since the outbreak of political violence in 1969.
Since 1994 there has been a shaky and intermittent cease-fire among the paramilitary groups in Northern Ireland. The 1998 Good Friday agreement is the most recent accord. What happened to cause it? The English invasion sparked a lot of anti-English sentiment and led to constant fighting between the two groups. Also, the English exerted complete control and did not help the Irish during the Great Famine between 1845 and 1852, which caused riots and sparked other prejudiced movements and laws. Were there any significant figures in this? English King William III asserted complete control over the Irish in 1691.
Eamon de Valera was the leader of the Sinn Fein, a political party which advocated Irish independence. He was almost executed for participating in an uprising in Dublin. Michael Collins was the leader of the IRA (the Irish Republican Army) who fought against the British for the Government of Ireland Act in 1920. Bringing the IRA fight into the international spotlight was Bobby Sands, an IRA member who died while on a hunger strike in a Belfast prison to protest his status as a common prisoner, rather than a political one.