DUBLIN -- Much of the world is turning green Wednesday for St. Patrick's Day, the annual celebration of all hues of Irishness.
Half a million people were forecast to line the 3-kilometer route of the flagship Dublin parade, which is exploring the theme "The Extraordinary World." It is a nod to Ireland's increasing multiculturalism - as well as the past two centuries' global spread of the Irish.
Click the player to watch the Ireland tourism video, "Who was St. Patrick?"
This year Ireland also is pushing itself especially hard as a tourist destination as the country faces its worst recession since the Great Depression, with double-digit unemployment and net emigration for the first time in 15 years.
St. Patrick's Day is Ireland's first major tourist event of the year, packing hotels and pubs with visitors seeking an all-night party. Ireland's weeklong festival gets bigger each year, with more than 100 parades Wednesday in cities, towns and villages across the island of 6 million.
The Tourism Ireland agency wangled a deal for major world landmarks - including the Sydney Opera House, London Eye, Toronto's CN Tower and New York's Empire State Building - to be bathed in green floodlights as part of a marketing push on four continents.
Virtually the entire Irish government left the country this week to press the flesh of foreign leaders and corporate kingpins in 23 countries in hopes of rekindling the investment wave that fueled Ireland's lost Celtic Tiger boom of 1994-2007.
Prime Minister Brian Cowen was meeting U.S. President Barack Obama at the White House, continuing Ireland's unique tradition of annual access to perhaps the most powerful man on earth.
President Mary McAleese, Ireland's ceremonial head of state who stayed at home to preside over the Dublin parade and her own St. Patrick's garden party, said the Irish had powerful allies in politics and business backed by 70 million people of Irish descent, half of them Americans.
"We are lucky to have such a large global family. It has proved itself to be a very precious and important resource in every generation," she said.
The Catholic Church, the once-dominant Irish faith, sought to remind revelers of the true story of Patrick: a Briton enslaved in his youth in Ireland who returned to spread Christianity throughout the pagan land in the 5th Century.
Bishop Seamus Hegarty's St. Patrick's Day message called for prayers for immigrants - both the Irish seeking jobs overseas and the Emerald Isle's own tens of thousands of newcomers from Eastern Europe, Africa and Asia who often work the longest hours for least pay.
"Mindful that St. Patrick was himself a migrant, we as a people are called to build a society that is truly inclusive, a society that is welcoming and respectful of people of different cultures, languages and traditions," Hegarty said.
"While our primary focus must be to ensure that we prevent another lost generation, we must also ensure that for those who decide to emigrate, they are neither abandoned nor forgotten," he said.
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