Alten was with John Moore in Sweden and Spain. He commanded the 2nd Flank Brigade in Moore's campaign though he missed the Battle of Corunna. He participated in the disastrous Walcheren expedition in the summer of 1809. He was soon employed once more in the Peninsula, and at the Battle of Albuera he commanded an independent KGL brigade. An incident in the battle highlights both the abilities and the limitations of Alten.