Rowley attended the Royal Naval Academy at Portsmouth in 1785 and joined his first ship in March 1789, serving in the West Indies.

Rowley returned to England at the beginning of 1795 and shortly after, was appointed to the 32-gun HMS Astraea, serving in the English Channel, where, on 10 April 1795, he assisted in the taking of the French 42-gun frigate, Gloire.

Rowley was promoted to Master and Commander of the bomb vessel HMS Terror in 1799 and fought in her at the Battle of Copenhagen in 1801.

[1] The expedition, comprising 19 vessels, including Vengeance, and 7,000 men, left Barbados on 2 February and arrived off Martinique four days later.

[3][4] Troops were put ashore at the Bay of Galion, Case de Navire and Sainte Luce, and by 16 March had all the island, save two forts, under control.

Casualties of battle, sickness and the need to maintain a garrison on Martinique, meant only 4800 troops could be spared but St Lucia was poorly defended.

[7] A small squadron was dispatched to capture the Saintes but Vengeance sailed with Jervis' main fleet to Guadeloupe, arriving in Gosier Bay on 10 April.

[12] Jervis was made aware of this on 5 June and immediately sent ships to Martinique for reinforcements while he and Grey set off in Boyne with Veteran in company.

[1] Shortly after his return home, Rowley was appointed to the 32-gun HMS Astraea, serving in the Channel, where, on 10 April 1795, he assisted in the capture of the French 42-gun frigate, Gloire.

[18] At 18:00, Astraea was close enough to her chase to open fire and a running battle ensued with the British frigate slowly gaining.

[17] In 1801, Terror was sent to the Baltic with a large force, under Admiral Sir Hyde Parker, to disrupt the league of armed neutrality, and took part in the attack on Copenhagen on 2 April.

[21] Terror was one of seven bomb vessels that Nelson had anchor outside the British line, off the large shoal known as the Middelgrund, from where they could throw their shells over the top, into the city.

[22] The fighting lasted for more than five hours,[23] after which Denmark agreed to suspend its armed neutrality and open its ports to British shipping.

Rowley tried to prevent his ship from sliding off into deep water by deploying her anchors but the situation was worsened when the sudden halting of the Laurel broke off part of her keel.

Laurel grounded with water up to the quarterdeck; the force of the collision snapping her masts and throwing the boats and guns overboard.

[27][28] In 1797 Rowley embarked upon a political career, following in the footsteps of his father and older brother, although his life at sea probably kept him from attending frequently.

He represented the constituency of Kinsale in the last Irish Parliament before the union with Great Britain which, despite his allegiance, he initially voted against.