The increasingly close relationship between London and Dublin is to be further cemented next week, when Michael Higgins becomes the first Irish president to pay a state visit to Britain, according to dpa. The four-day sojourn is a "milestone", said Irish Ambassador to London Daniel Mulhall, coming almost 100 years after Ireland effectively became independent from Britain. Higgins will receive the rare honour of addressing both houses of parliament and the even rarer privilege of being the guest of honour at two banquets hosted by Queen Elizabeth II at her home in Windsor Castle. It is the final seal on the recent transformation of relations between the neighbouring countries, burdened by centuries of bloody history. The signing of the Good Friday Agreement in 1998, which brought an imperfect peace to Northern Ireland, ushered in a new era of goodwill culminating in the queen visiting the Republic of Ireland for the first time in 2011. It took a long time for "signs of normality" to assert themselves after 1998, said Bernard Purcell, editor of the London-based newspaper Irish World. "But that seems to have happened at almost a geometric rate since the queen's visit." Two years ago, the two countries issued a joint statement looking ahead to the next decade and agreeing to work together on economic growth, the conflict in Northern Ireland, and as EU partners. There are now annual meetings between London's permanent secretaries and Dublin's secretaries general - top civil servants - and this year ministers undertook their first joint trade mission, to Singapore. After the queen's visit "we were suddenly able to talk more freely to each other across everything," said a British Foreign Office spokesman. Old sensitivities and hang-ups were "put to one side," he said, "It felt palpable." Since England's Henry VIII - most famous for his six wives - first proclaimed himself king of Ireland in 1541, British-Irish relations had been fraught. Rebellions against English rule in the subsequent centuries were violently quelled and Ireland's mainly Catholic population was oppressed and dispossessed by its Protestant overlords. Firmly impressed upon Irish folk memory is the devastating potato famine of the late 1840s, when around a million Irish died and another million emigrated. The disaster was compounded by the economic policies of a seemingly callous British government. After a three-year war, Ireland essentially won independence from Britain in 1922. However, the island was partitioned and the Protestant-dominated north-east remained part of Britain as Northern Ireland. It is "almost entirely" because of the difficult legacy of Northern Ireland, that relations between Dublin and London were strained for so long, said Purcell. The revolutionary Irish Republican Army (IRA) carried out a decades-long terrorist campaign against Britain in an effort to unite Ireland, while Protestant unionist paramilitaries also committed atrocities. In 1985, the IRA attempted to kill late British former premier Margaret Thatcher when they bombed the hotel she was staying in. Six years earlier the group murdered the queen's cousin Lord Mountbatten. This personal history made it all the more meaningful when in 2012 the queen publicly shook the hand of Martin McGuinness, a former IRA commander who is now the deputy First Minister of Northern Ireland. But despite the political estrangement of the past, British and Irish culture has always been closely intertwined, and the countries have also become key trading partners over the past decades. There are around 400,000 Irish people living in Britain - as well as millions more of Irish descent - and a similar number of British people living in Ireland. Many authors considered by the British as part of their own literary tradition - Oscar Wilde, George Bernard Shaw, Jonathan Swift - are in fact Irish-born. And it runs both ways, said Mulhall: "For Irish people, Shakespeare hardly counts as a foreign author." Higgins' visit is designed to reflect these ties and allow him to meet as many Irish people as possible. He is to visit Stratford upon Avon, Shakespeare's birthplace, attend an Irish-themed concert at the Royal Albert Hall and inspect a racing stables - horse racing being a particular passion of the queen as well as millions of Irish and British citizens. But for Purcell, the best illustration of how relaxed the countries have become with each other came in the form of an Irish World front page in September. It featured a story on the queen's invitation to the centenary commemorations of the 1916 Easter Rising in Dublin - the rebellion which set Ireland on the path to independence - alongside another about the England cricket team, captained by an Irishman, beating Ireland at the captain's home ground in Malahide, in Dublin. Such a front page for an Irish newspaper would until very recently have been "unthinkable", said Purcell.