 The Irish Battalions remained on active service with the Army of Portugal through the sieges of Ciudad Rodrigo and Almeida, the Battle of Bussaco and the full course of the advance to the Lines of Torres Vedras.Napoleon had decreed on 28 October 1810 that the Irish Regiment should be reduced to two battalions, whereby the 2nd & 3rd Battalions would become the 2nd Battalion.The reformed 2nd Battalion saw hard service as part of the rearguard on the retreat from Lisbon.