In 1803, a second battalion was reformed and the following year deployed to Ireland. In 1806, the 1st battalion was sent to garrison the former Dutch settlement of the Cape of Good Hope, then joined the 1807 River Plate expedition under Sir Samuel Auchmuty, fighting at Montevideo in February and Buenos Aires in July. The battalion was deployed to India in 1808 and the following year its flank companies took part in an expedition to the Persian Gulf.