Throughout his career in Irish politics, O'Connell was able to gain a large following among the Irish masses in support of him and his Catholic Association. O'Connell's main strategy was one of political reformism, working within the parliamentary structures of the British state in Ireland and forming an alliance of convenience with the Whigs. More radical elements broke with O'Connell to found the Young Ireland movement.
O'Connell was born at Carhan near Cahersiveen, County Kerry, to the O'Connells of Derrynane, a once-wealthy Roman Catholic family, that had been dispossessed of its lands. Among his uncles was Daniel Charles, Count O'Connell, an officer in the Irish Brigades of the French Army. A famous aunt was Eibhlín Dubh Ní Chonaill, while Sir James O'Connell, 1st Baronet, was his younger brother. Under the patronage of his wealthy bachelor uncle Maurice "Hunting Cap" O'Connell. O'Connell was first sent with his brother Maurice to Reddington Academy at Long Island, near Queenstown (Cobh) They both studied at Douai in France from 1790 and O'Connell was admitted as a barrister to Lincoln's Inn in 1794, transferring to Dublin's King's Inns two years later. In his early years, he became acquainted with the pro-democracy radicals of the time and committed himself to bringing equal rights and religious tolerance to his own country.
While in Dublin studying for the law, O'Connell was under his Uncle Maurice's instructions not to become involved in any militia activity. When Wolfe Tone's French invasion fleet entered Bantry Bay in December 1796, O'Connell found himself in a quandary. Politics was the cause of his unsettlement. Dennis Gwynn in his Daniel O'Connell: The Irish Liberator suggests that the unsettlement was because he was enrolled as a volunteer in defence of Government, yet the Government was intensifying its persecution of the Catholic people—of which he was one. He desired to enter Parliament, yet every allowance that the Catholics had been led to anticipate, two years previously, was now flatly vetoed.
As a law student, O'Connell was aware of his own talents, but the higher ranks of the Bar were closed to him. He read the Jockey Club as a picture of the governing class in England and was persuaded by it that, "vice reigns triumphant in the English court at this day. The spirit of liberty shrinks to protect property from the attacks of French innovators. The corrupt higher orders tremble for their vicious enjoyments."
O'Connell's studies at the time had concentrated upon the legal and political history of Ireland, and the debates of the Historical Society concerned the records of governments, and from this he was to conclude, according to one of his biographers, "in Ireland the whole policy of the Government was to repress the people and to maintain the ascendancy of a privileged and corrupt minority."