A vigorous opponent of the taxation of America, Barré displayed his mastery of invective in his championship of the American cause, and the name "Sons of Liberty," which he had applied to the colonists in one of his speeches, became a common designation of the American organizations directed against the Stamp Act, as well as of later patriotic clubs. His appointment in 1782 to the treasurership of the navy, which carried with it a pension of £3200 a year, at a time when the government was ostensibly advocating economy, caused great discontent; subsequently, however, he received from the younger Pitt the clerkship of the pells, a sinecure for life, in place of the pension, which thus was saved to the public. Becoming blind, he retired from office in 1790 and died on July 20, 1802.
The son of Peter Barré, a Huguenot refugee living in Dublin, who was High Sheriff of Dublin (1756). Isaac Barre was an army officer and later entered politics under the wing of Lord Shelburne, particularly distinguishing himself as formidable orator and champion of the American colonists. After studying at Trinity College Dublin, he joined the 32nd regiment of foot as an ensign in 1746, and was promoted to Lieutenant in 1755 and Captain in 1756. He served under Wolfe on the Rochefort expedition of 1757, when he first met Shelburne, and afterwards in Canada where he was appointed Adjutant-General, fighting at both Louisbourg (1758) and Quebec (1759). In the Quebec expedition, in which his patron Wolfe was killed, Barré was wounded by a bullet in the cheek and lost the use of his left eye, and was among the group gathered around the dying Wolfe, immortalised in Benjamin West's celebrated pictures of the scene. Returning to England in September 1760, he failed to gain promotion in the army despite his achievements, and turned to Shelburne for help. After undertaking a tour of Shelburne's Irish estates, he was advanced to lieutenant-colonel of the regiment of 106th Foot at Shelburne's instigation, and in 1763 was appointed to the lucrative posts of Adjutant-General to the British Army and Governor of Stirling Castle. Shelburne, introduced him to Lord Bute and brought him into parliament for his borough of Chipping Wycombe (1761-1774) and then for Calne (1774-1790). One of the few self-made soldiers in parliament, Barré became one of Shelburne's principal supporters in the House of Commons. In his first political speech he made a vehement attack on the absent War Minister William Pitt, renewing this assault the next day to Pitt's face, which caused a sensation and set the tone of a long and colourful parliamentary career in which he acquired a fearsome reputation as an orator.
Barré's knowledge of North America (he was one of the few politicians with friendships among the American mercantile classes) made him a champion of the colonists, whom he famously described as 'the sons of liberty' when opposing the intended Stamp Act that had been passed on 6 February 1765. An example of his fiery oratory was his response to Charles Townsend's observation when introducing the American Stamp Act resolutions that the colonies should 'contribute to the mother country which had planted, nurtured and indulged them' to which he famously answered:
'They planted by your care! No, your oppressions planted them in America. They fled from your tyranny to a then uncultivated, inhospitable country, where they exposed themselves to almost all the hardships to which human nature is liable, and among others to the cruelties of a savage foe and actuated by principles of true English liberties, they met all hardships with pleasure compared with those they suffered in their own country from the hands of those who should be their friends'.
In the Stamp Act crisis Barré not only championed repeal but also followed Pitt in opposing the complete right of taxation as stated in the Declaratory Act. His efforts against the Stamp Act were commemorated in America with the founding of the Pennsylvania town of Wilkes-Barré in 1769. Walpole described him as 'a black robust man of a military figure, rather hard-favoured than not young, with a peculiar distortion on one side of his face, which it seems was owing to a bullet lodged loosely in his cheek, and which gave a savage glare to one eye'.