The career of Henry Bennet, 1st earl of Arlington, as secretary of state for the southern department in the first half of the Restoration period coincides with a very important time in Irish history. The political decisions made during the Restoration, and in particular with regards to the land settlement, set up the foundations of Protestant ascendancy that existed for the following two centuries. The role of the secretary of state then, as lynchpin between Charles II, his bureaucracy and his westerly kingdom, was one of great importance. Whilst Irish contact with the court at Whitehall could circumnavigate the secretary, the vast majority of official Irish business had to go through his hands. At the same time, Arlington made use of his position to get an Irish estate at Portarlington in the midlands and, whilst he never made a real success of it, his influence and the manner in which it was established will tell us something of his attitude towards Ireland. This chapter will consider Arlington’s influence on Ireland and to what extent he left his stamp on Irish affairs in the early Restoration period and in particular how his management of Irish business influenced, assisted or indeed might have obstructed the application of royal policy in Ireland.