This is usually explained as a result of invasions by Celts from the continent.However, other research has postulated that the culture developed gradually and continuously, and that the introduction of Celtic language and elements of Celtic culture may have been a result of cultural exchange with Celtic groups in southwest continental Europe from the Neolithic to the Bronze Age. Ptolemy, in 100 AD, recorded Ireland's geography and tribes.Although promised a repeal of the Test Act, Catholics were not granted full rights until Catholic Emancipation was attained throughout the new UK in 1829.This was followed by the first Irish Reform Act 1832, a principal condition of which was the removal of the poorer Irish freeholders from the franchise.In 1922, after the Irish War of Independence and the Anglo-Irish Treaty, most of Ireland seceded from the United Kingdom to become the independent Irish Free State, which after the 1937 constitution, began to call itself Ireland.
Protestant domination of Ireland was confirmed after two periods of war between Catholics and Protestants in 1641--91.
Four main types of Irish Megalithic Tombs have been identified: dolmens, court cairns, passage tombs and wedge-shaped gallery graves.
In Leinster and Munster, individual adult males were buried in small stone structures, called cists, under earthen mounds and were accompanied by distinctive decorated pottery.
The Crown did not attempt to assert full control of the island until the rebellion of the Earl of Kildare threatened English hegemony.
Henry VIII proclaimed himself King of Ireland and also tried to introduce the English Reformation, which failed in Ireland.