The Sheares Brothers, Henry (1753–98), and John (1756–1798) were Irish lawyers and members of the Society of United Irishmen, who died in the 1798 rebellion.
The Sheares brothers were the sons of Henry Sheares, a liberal banker from Cork who also sat in the Irish Parliament for the Borough of Clonakilty. Henry attended Trinity College Dublin, bought an officer's commission and then studied as a lawyer, being called to the bar as a barrister in 1790. John had qualified as a barrister in 1788. Their father had died in 1776, leaving a large income of £1,200 p.a.
In 1792 the brothers went to Paris and were swept away by the popular enthusiasms of the French revolution. They met leaders such as Brissot and Roland, both of whom were to be executed in 1793. In particular they witnessed the introduction of the guillotine, on which 1,400 were to die in 1792. On the boat from France to England they met Daniel O'Connell (then a student) who was disgusted by the increasingly bloodthirsty nature of the revolution. O'Connell remained an advocate of non-violence thereafter.
They joined the United Irish movement on their return to Dublin in January 1793, when it was still legal. However, France declared war on Britain (and by extension, on Ireland) in February 1793. The Society's initial aims of securing 1) Catholic Emancipation and 2) universal suffrage were unsuccessful, amounting to the administration's 1793 Relief Act. Its stance became more radical, and in turn the Irish administration feared a group inspired by France, banning it in 1794. The Sheares brothers principally organised the movement in Cork, while continuing with their legal careers. A Mr. Conway, one of their keenest members in Cork, informed the administration of their activities. During 1793 the brothers also joined the Dublin Society of the United Irishmen, where another spy, Thomas Collins, passed on their names. Their two other less famous brothers had enlisted in the British army and were killed in action. On the arrest of most of the United Irish "Directory" members in March 1798, John was chosen as a replacement on the approach to the outbreak of rebellion. His main act at this point was to decide on the date - 23 May.