This officer entered the army on the 15th of December 1777, as a cornet in the fourth regiment of horse, now the seventh dragoon guards; and on the 9th of July 1779, he exchanged to an ensigncy in the Coldstream guards, in which he was promoted to a lieutenancy, with the rank of captain, on the 12th of December 1781. On the 25th of June 1785, he was advanced to the rank of major of the twelfth dragoons, and on the 16th of September 1786, exchanged into the thirteenth foot, of which regiment he was appointed lieut.-colonel on the 16th of June 1789. Lieut.-Colonel Cradock commanded the thirteenth regiment in the West Indies, and on his return, in 1792, was appointed quartermaster-general in Ireland, where he was specially employed by Government in many of the disturbed counties. He went a second time to the West Indies, in the command of the second battalion of grenadiers, under the orders of General Sir Charles (afterwards Earl) Grey, and was present at the reduction of Martinique (where he was wounded), St. Lucia, Guadaloupe, and at the siege of Fort Bourbon. Before the reduction of the second battalion of grenadiers in the West Indies he was appointed by Sir Charles Grey to be his aide-de-camp, and on his return to England he received the thanks of Parliament for his services. On the 26th of February 1795, Lieut.-Colonel Cradock received the brevet rank of colonel, and on the 16th of April following was appointed colonel of the one hundred and twenty-seventh regiment, which was disbanded in 1798, when he was placed on half pay. On the 1st of January 1798, Colonel Cradock was advanced to the rank of major-general, and served as quartermaster-general in Ireland during the rebellion of that year; was under the command of Lieut.-General Gerard (afterwards Viscount) Lake at the affair with the rebels at Vinegar Hill, and in the subsequent movements in the county of Wexford. Major-General Cradock accompanied Earl Cornwallis as quartermaster-general in his lordship’s march against the French forces that landed in Killala under General Humbert, and was severely wounded in the action at Ballynahinch, when the French and rebel force were defeated, and laid down their arms.