On 4 February 1755 Boscawen was promoted
vice admiral and given command of a squadron on the
North American Station. A squadron of partially disarmed French ships of the line were dispatched to
Canada loaded with reinforcements and Boscawen was ordered to intercept them. The French
ambassador to London, the
Duc de Mirepoix had informed the government of George II that any act of hostility taken by British ships would be considered an act of war. Thick fog both obstructed Boscawen's reconnaissance and scattered the French ships, but on 8 June Boscawen's squadron sighted the
Alcide,
Lys and
Dauphin Royal off
Cape Ray off
Newfoundland. In
the ensuing engagement the British captured the
Alcide and
Lys but the
Dauphin Royal escaped into the fog. Amongst the 1,500 men made prisoner was the captain of the
Alcide. For M. de Hocquart it was the third time that Boscawen had fought him and taken his ship. Pay amounting to £80,000 was captured aboard the
Lys. Boscawen, as vice-admiral commanding the squadron, would have been entitled to a sizeable share in the
prize money. The British squadron headed for
Halifax to regroup but a fever spread through the ships and the Vice-admiral was forced to return to England. Boscawen returned to the
Channel Fleet and was commander-in-chief
Portsmouth during the trial of Admiral
John Byng. Boscawen signed the order of execution after the King had refused to grant the unfortunate admiral a pardon. Boscawen was advanced to
Senior Naval Lord on the Admiralty Board in November 1756 but then stood down (as Senior Naval Lord although he remained on the Board) in April 1757, during the
caretaker ministry, before being advanced to Senior Naval Lord again in July 1757.
Siege of Louisburg In October 1757 Boscawen was second in command under Admiral
Edward Hawke. On 7 February 1758 Boscawen was promoted to
Admiral of the blue squadron. and ordered to take a fleet to North America. Once there, he took naval command at the
siege of Louisburg during June and July 1758. On this occasion rather than entrust the land assault to a naval commander, the army was placed under the command of General
Jeffrey Amherst and Brigadier
James Wolfe. The siege of Louisburg was one of the key contributors to the capture of French possessions in
Canada. Wolfe later would use Louisburg as a staging point for the
siege of Quebec. The capture of the town deprived the French of the only effective naval base that they had in Canada, as well as leading to the destruction of four of their ships of the line and the capture of another. On his return from North America Boscawen was awarded the Thanks of both
Houses of Parliament for his service. The King made Boscawen a
Privy Counsellor in recognition for his continued service both as a member of the Board of Admiralty and commander-in-chief.
Battle of Lagos |right|thumb In April 1759 Boscawen took command of a fleet bound for the Mediterranean. His aim was to prevent another
planned invasion of Britain by the French. With his flag aboard the newly constructed of 90 guns he blockaded
Toulon and kept the fleet of Admiral
de le Clue-Sabran in port. In order to tempt the French out of port, Boscawen sent three of his ships to bombard the port. The guns of the batteries surrounding the town drove off the British ships. Having sustained damage in the action and due to the constant weathering of ships on blockade duty Boscawen took his fleet to
Gibraltar to refit and resupply. On 17 August a frigate that had been ordered to watch the
Straits of Gibraltar signalled that the French fleet were in sight. Boscawen took his available ships to sea to engage de la Clue. During the night the British chased the French fleet and five of de la Clue's ships managed to separate from the fleet and escape. The others were driven in to a bay near
Lagos,
Portugal. The British overhauled the remaining seven ships of the French fleet and engaged. The French line of battle ship began a duel with
Namur but was outgunned and
struck her colours. The damage aboard
Namur forced Boscawen to shift his flag to of 80 guns. Whilst transferring between ships, the small boat that Boscawen was in was hit by an enemy cannonball. Boscawen took off his wig and plugged the hole. Two more French ships, and escaped during the second night and on the morning of 19 August the British captured and and drove the French flagship and ashore where they foundered and were set on fire by their crews to stop the British from taking them off and repairing them. The five French ships that avoided the battle made their way to
Cádiz where Boscawen ordered Admiral Thomas Broderick to blockade the port. ==Final years, death, and legacy==