As the Queen prepares for her four-day state visit to Ireland on Tuesday, BBC royal correspondent Nicholas Witchell explores the chequered history between the British monarchy and its neighbour.

The relationship between the Crown and Ireland has been one of the longest and most difficult in the history of Britain's monarchy.

Indeed attitudes to the Crown have been a defining, sometimes contradictory, and at times almost obsessive feature in the development of the Irish state.

Let us apply some definitions here. "The Crown" is the presence which, to very many generations of Irish people, came to symbolise the subjugation of their lands by distant and uncaring governments in London.

'Merciless exploitation'

Those governments presented themselves as "His Majesty's" or "Her Majesty's" governments....