10. Grace Kelly - The future Princess of Monaco may be a bit overdramatic as Georgie Elgin, singer Frank Elgin's (Bing Crosby) long-suffering wife, but we feel the need to pay homage to the unforgettable film star, whose Irish roots are traced to Louisburgh, Co. Mayo.
9. Thomas Mitchell - This great American character actor and first generation Irish-American (pictured in a scene from 'High Noon') can be seen in classics such as 'Gone with the Wind' (he plays Scarlett O'Hara's father) and 'It's a Wonderful Life' (he's Uncle Billy). His Oscar win came for his role in John Ford's classic western, 'Stagecoach,' in which Mitchell plays the drunken Doc Boone.
8. Anjelica Huston - Huston, who spent much of her childhood on her father's Galway estate, has said of the Emerald Isle: 'I don't feel anywhere else in the world the way I feel in Ireland. I feel at home there.' But with her Oscar-winning role in 'Prizzi's Honor,' Huston gets in touch with her Italian roots, creating the unforgettable Maerose Prizzi, daughter of a powerful mobster.
7. Jimmy Cagney - Though he's famous for his tough-guy gangster roles, Cagney's Oscar win came from his arguably best performance as song-and-dance man George M. Cohan in 1942's 'Yankee Doodle Dandy.'
6. Jennifer Connelly - Connelly gave a stellar performance as Alicia Nash in Ron Howard's Academy Award-winning film. Her portrayal of the wife of schizophrenic and mathematical genius John Nash not only earned Connelly an Oscar, but also a Golden Globe, BAFTA and AFI.
5. Kevin Kline - In 'A Fish Called Wanda,' Kline brilliantly portrays con artist Otto West. Kline, who is both Irish and Jewish, explained the complexity of the role that won him the Oscar: 'There seemed to me to be something so illogical about Otto; he was completely brain-dead stupid but then he could crack a safe, scale tall buildings and do seemingly impossible feats.'
4. Maureen Stapleton - A first-generation Irish-American, Stapleton is one of the elite acting Triple Crown winners, earning an Oscar, Tony and Emmy during her career. Stapleton's Oscar win came with her performance in 1981's 'Reds' (pictured). Stapleton plays Emma Goldman, the Russian-born anarchist and supporter of the Bolshevik Revolution.
3. Spencer Tracy - An Irish-American and devout Catholic, Tracy was the first actor to win back-to-back Oscars (1938 Best Actor for 'Captains Courageous' and 1939 Best Actor for 'Boys Town').
2. Gregory Peck - After four Oscar nominations, Peck finally nabbed the award for his riveting performance as Atticus Finch in 'To Kill a Mockingbird.' In this legendary performance, Peck helps bring Harper Lee's Pulitzer Prize-winning novel to life in his role as the Depression-era lawyer who defends a black man accused of raping a white woman in a racially tense town.
1. Sean Penn - It's tough to compare 1940s film performances to those of today, but it wasn't difficult to identify Sean Penn's depiction of Jimmy Markum in Mystic River, a film based on the book by Irish-American Dennis Lehane, as one of the best. In this Clint Eastwood-directed film, Penn, who has Irish roots on his mother's side, electrifies in his gut-wrenching performance as a father seeking revenge on his daughter's murderer. The actor went on to win another much-deserved leading actor Oscar in 2009 for 'Milk.'
Slideshow will continue in 5 secondsSKIP