After taking part in an expedition to Lisbon to support the Portuguese in the face of a Spanish threat, he saw action as captain of the third-rate HMS Norfolk at the Battle of Toulon during the War of the Austrian Succession.

[1] The Britannia was at this time the flagship of Admiral Sir John Norris, and Forbes sailed with him on an expedition to Lisbon to support the Portuguese in the face of a Spanish threat.

Promoted to captain on 24 October 1737, Forbes became commanding officer of the 20-gun sixth-rate HMS Port Mahon and was sent to serve on the Coast of Ireland Station in 1738.

[1] Forbes was given command the 80-gun third-rate HMS Norfolk in 1742 and saw action at the Battle of Toulon on 11 February 1744 during the War of the Austrian Succession.

[3] He followed the example of Admiral Thomas Mathews, who was aboard the second-rate HMS Namur, and was one of the few captains who really bore down on the enemy.

[1] In Summer 1746 he was called upon to give evidence at the court-martial of Vice-Admiral Richard Lestock during the recriminations after the battle.

[3] Suffering from poor health he rejected offers to take a command in the East Indies and then a governorship in New York in 1754.

[3] He died at his home in Savile Row on 10 March 1796[13] and was buried in the Essex family vault in the parish church of St Mary's Watford next to his wife.