Says the _Weekly Post Boy_, of August 27th, in that year: "His Majesty's ship _Launceston_, commanded by the brave Commodore Warren (whose absence old Oceanus seems to lament), being now sufficiently repaired, will sail in a few days in order once more to pay some of His Majesty's enemies a visit." And it winds up with this burst: _"The sails are spread; see the bold warrior comes To chase the French and interloping Dons!"_ It was in the following year that he signally distinguished himself in the historic Siege of Louisbourg, winning himself a promotion to the rank of Rear Admiral of the Blue, and a knighthood as well! It may seem a far cry from Greenwich, New York, to Louisbourg, but we cannot pass over the incident without sparing it a little space.

Let me beg your patience,--quoting, in my own justification, no less a historian than James Grant Wilson: "This Commodore Warren was one of those indefatigable and nervous spirits who did such wonders at Louisbourg, and it is with particular pride that his achievement should be remembered in a history of New-York, as he was the only prominent New-Yorker that contributed to Massachusetts' greatest Colonial achievement." The capture of Louisbourg may be remembered by some history readers as a part of that English-French quarrel of 1745, commonly known as "King George's War," and also as the undertaking described by so many contemporaries as "Shirley's Mad Scheme." The scheme _was_ rather mad; hence its appeal to Peter Warren, who was exceedingly keen about it from the beginning.
Louisbourg was a strong French fortress on Cape Breton Island, commanding the gulf of the St.Lawrence.Its value as a military stronghold was great, and besides it had long been a fine base for privateers, and was a very present source of peril to the New England fishermen off the Banks.

As far back as 1741 Governor Clarke of New York had urged the taking of this redoubtable French station, but it fell to the masterful Shirley, Governor of Massachusetts, finally to organise the expedition.

He had Colonial militia to the tune of four thousand men, and he had Colonial boats,--nearly a hundred of them,--and he had the approval of the Crown (conveyed through the Duke of Newcastle); but he wanted leaders.

For his land force he chose General Pepperrill, an eminently safe and sane type of soldier; for the sea he, with a real brain throb, thought of Captain Peter Warren.
Francis Parkman says: "Warren, who had married an American woman and who owned large tracts of land on the Mohawk, was known to be a warm friend to the provinces." He was at Antigua when he received the Governor's request that he take command of the "Mad Scheme." Needless to say, the Captain was charmed with the idea, but he had no orders from the King! He refused almost weeping, and for two days was plunged in gloom.