ogan began his military
career as a cornet of horse under William III. at the Boyne, and, with the
regiment now known as the 5th (Royal Irish) Lancers, made the campaigns in
the Low Countries. In the course of these years he attracted the notice of
Marlborough. In 1701 Cadogan was employed by him as a staff officer in the
complicated task of concentrating the grand army formed by contingents from
[v.04 p.0932] multitudinous states, and Marlborough soon made the young
officer his confidential staff officer and right-hand man. His services in
the campaign of 1701 were rewarded with the colonelcy of the famous
"Cadogan's Horse" (now the 5th Dragoon Guards). As quartermaster-general,
it fell to his lot to organize the celebrated march of the allies to the
Danube, which, as well as the return march with its heavy convoys, he
managed with consummate skill. At the Schellenberg he was wounded and his
horse shot under him, and at Blenheim he acted as Marlborough's chief of
staff. Soon afterwards he was promoted brigadier-general, and in 1705 he
led "Cadogan's Horse" at the forcing of the Brabant lines between Wange and
Elissem, capturing four standards. He was present at Ramillies, and
immediately afterwards was sent to take Antwerp, which he did without
difficulty. Becoming major-general in 1706, he continued to perform the
numerous duties of chief staff officer, quartermaster-general and colonel
of cavalry, besides which he was throughout constantly employed in delicate
diplomatic missions. In the course of the campaign of 1707, when leading a
foraging expedition, he fell into the hands of the enemy but was soon
exchanged. In 1708 he commanded the advanced guard of the army in the
operations which culminated in the victory of Oudenarde, and in the same
year he was with Webb at the action of Wynendael. On the 1st of January
1709 he was made lieutenant-general. At the siege of Menin in this year
occurred an incident which well illustrates his qualifications as a staff
officer and diplomatist. Marlborough, riding with his staff close to the
French, suddenly dropped his glove and told Cadogan to pick it up. This
seemingly insolent command was carried out at once, and when Marlborough on
the return to camp explained that he wished a battery to be erected on the
spot, Cadogan informed him that he had already given orders to that effect.
He was present at Malplaquet, and after the battle was sent off to form the
siege of Mons, at which