U.S. President Barack Obama's story is certainly out of the ordinary. But then everything about this presidential front-runner seems woven out of the stuff dreams are made of.

 Though his father was Kenyan, Obama hardly knew the man and grew up in an all-white family, which clearly marked him as different from an early age.

In America’s highly-charged racial environment Obama is considered an African American, even though his formative years and early life was all spent with his white relatives.

Certainly Obama himself never seemed to believe he would be perceived as anything but an African American. In his moving memoir "Dreams from My Father" he recounts many racial slurs aimed at him throughout his young life and the impact they had on him.

Obama’s father disappeared back to Kenya when he was just two, and he only ever saw him again once. His father, Barack senior, a one-time goat herder, accomplished the astonishing feat of acquiring a graduate degree in economics from Harvard.

He later married Ann Dunham when she was just 18 but left her two years later.  Barack Senior married three more times and fathered eight children in all but was killed in a traffic accident.

Obama’s formative years were in Hawaii living with his grandparents, where an African American could fit in easily with the many other ethnic groups in the Hawaiian melting pot.

While no doubt his defining experiences have been as a black man in the U.S., it is partly an Irish American experience that shaped his early life.

Those roots of his mother’s family were Irish stretching back to Falmuth Kearney from Moneygall, Co. Offaly, who sailed to America in the year of 1850 at just 19 years old.

Researchers initially thought that Falmuth, Obama’s great-great-great grandfather, was the only one in his family to emigrate. However, records brought forward by Ancestry.com reveal that other Kearney family members had been in America since the 1790s.

“One ancestor, Falmuth’s paternal uncle, Francis, had in fact bequeathed land to his brother, Falmuth’s father Joseph, with the condition that he emigrate in order to inherit. He did so along with his wife Phoebe and four children, including Falmuth,” Ancestry.com reports.                    

Falmuth was a Protestant, obviously from a reasonably respectable family, and the family homestead stood until quite recently back in Offaly. In the 1880 federal census Kearney was described as working as a farm hand in Ohio.

He disappears off the map soon after, but his great-grandson, Stanley Dunham, is Obama’s grandfather, and still alive in Hawaii.

Unlike, say, Obama’s wife Michelle, who grew up in a black neighborhood in Chicago and took a conventional path, surrounded by fellow African Americans in a tight knit neighborhood, Obama is the sum of many different ethnic experiences.

His time living in Indonesia, in Hawaii and later in Illinois mark him as a man of the world from an early age, with more experience of the complexity of the world than most Americans.

Mixed in there is an Irish component, not all that unusual when we examine the history of African Americans and Irish. As Peter Quinn pointed out in "Searching for Jimmy," his excellent book on the Irish in New York, Irish and blacks lived cheek-by-jowl in the years after the Famine emigrants first came ashore. Inter-marriage was quite common.

While Obama is not of that background directly, his mixed roots remind us of an America that is far more complex ethnically than the straightforward narrative of white folk, black folk and brown folk, with some Asians thrown in that is usually put forward.

Like everything else about America, his success to date makes us rethink ourselves, which is no bad thing.