Thomas Pelham, 2nd Earl of Chichester PC, PC (Ire), FRS, styled The Honourable Thomas Pelham from 1768 until 1783, The Right Honourable Thomas Pelham from 1783 to 1801, and then known as Lord Pelham until 1805, was a British Whig politician. He notably held office as Home Secretary under Henry Addington from 1801 to 1803.

His or Her Majesty's Privy Council in Ireland, commonly called the Privy Council of Ireland, Irish Privy Council, or in earlier centuries the Irish Council, was the institution within the Dublin Castle administration which exercised formal executive power in conjunction with the chief governor of Ireland, who was viceroy of the British monarch. The council evolved in the Lordship of Ireland on the model of the Privy Council of England; as the English council advised the king in person, so the Irish council advised the viceroy, who in medieval times was a powerful Lord Deputy. In the early modern period the council gained more influence at the expense of the viceroy, but in the 18th century lost influence to the Parliament of Ireland. In the post-1800 United Kingdom of Great Britain and Ireland, the Irish Privy Council and viceroy Lord Lieutenant had formal and ceremonial power, while policy formulation rested with a Chief Secretary directly answerable to the British cabinet. The council comprised senior public servants, judges, and parliamentarians, and eminent men appointed for knowledge of public affairs or as a civic honour.