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July 2024
3min read

The Treaty of Utrecht ending the War of the Spanish Succession in 1713 cost France heavily in the New World, but its smooth-talking diplomats salvaged one strategic point. This was Cape Breton Island, a rugged, lonely bit of real estate jutting out into the Atlantic Ocean off the tip of Nova Scotia. There France built the fortress of Louisbourg, renowned in the early eighteenth century as the strongest in North America and perhaps in the world.

Some twenty miles southeast of what is now the island city of Sydney, a narrowgated harbor faced the North Atlantic. About two miles long from northeast to southwest, with an average width of half a mile, the bay was usually clear of ice the year round and sheltered from ocean storms by two necks of land that pinched the entrance to less than a mile, although rocks and shoals restricted the navigable passage to less than half that. Near the middle of the harbor mouth sat a small island.

The shoreline was low and rock-strewn, lashed by heavy surf nine days out of ten, and blanketed by heavy fog for weeks at a time. The sea itself was a great moat, the coast a fogbound lee shore too dangerous for heavy warships to close within effective bombardment range.

After the French military engineers sited the fort on the southern headland, work went slowly. The project so taxed the French treasury that King Louis XV was said to have remarked that someday he expected to look out the window at Versailles and see the walls of Louisbourg thrusting above the horizon.

The walls of this typical eighteenth-century stronghold enclosed fifty-seven acres between the seashore and inner harbor that contained a complete town that eventually housed four thousand people, exclusive of the garrison. The most massive portion was on the land side facing south, an earth-filled wall twelve hundred yards long, thirty feet high, revetted with solid masonry a foot thick and anchored at each end with bastions. The biggest of Louisbourg’s bastions—the King’s Bastion—contained in its gorge a strongly built stone structure that was the largest building in North America at the time: four stories high and three hundred and sixty feet long. The enclosure had emplacements for 148 guns, although never more than 90 were in position.

On the island off the tip of the peninsula a powerful battery covered the channel, and another one, called the Grand Battery or Batterie Royale, swept the entrance head-on. When completely armed—it never really was—Louisbourg could mount more than two hundred heavy guns and twenty huge mortars.

The imposing facade, however, had fatal flaws. It was dominated by a series of low hills about half a mile to the southwest, from which besiegers could command the wall. Since the French didn’t believe heavy guns could be moved through miles of swamp to the position, they didn’t bother to secure it.

Of greater concern was shoddy construction. Corrupt colonial officials diverted the solid stone masonry sent from France and replaced it with inferior stone. Sea sand and seawater were used in the mortar, producing a mix that never set properly. Long before construction was finished, older portions of the walls had begun to deteriorate, and the revetments were so unsteady that in action they gave way under concussion of the fort’s own guns.

In 1744 war broke out again between France and England, and French privateers based in Louisbourg soon were harrying the main trade route between New England and Britain. When the former raised troops and asked the home government to help out, the latter offered a protecting fleet for any force the colonists might send against Louisbourg.

The governor of Massachusetts recruited an army of four thousand wild, undisciplined, but young and hardy New Englanders. The commander was a Kittery, Maine, merchant named William Pepperrell. His knowledge of military matters just about matched that of his troops, but Pepperrell displayed unexpected abilities.

Thrice-armed with the valor of ignorance, the expedition swarmed ashore at the end of April 1745 at an uncovered point three miles to the west of the fort. Blissfully unaware they were attempting the impossible, the New Englanders dragged siege guns through the impassable marsh on huge wooden skids, carrying ammunition and provisions on their backs, and set up shop overlooking the fortress. There they discovered the Grand Battery abandoned and its guns spiked; the attackers quickly occupied it and put gunsmiths to work clearing the touchholes. Within days five batteries were zeroing in on the King’s Bastion, while another took care of the island battery. On June 17, after a siege of six weeks, Louisbourg surrendered.

Colonial elation was shortlived. At the end of the war Louisbourg was returned to France, to the huge disgust of New England, which never forgave the home government.

Eight years later the old antagonists squared off for the final round of a worldwide struggle. Early reverses delayed British efforts in America, but in 1758 an army of fourteen thousand regulars backed by a huge fleet set out for Louisbourg. The campaign was, in many ways, a repeat of 1745 but more professionally conducted under the driving leadership of a scrawny, red-headed brigadier named James Wolfe. After a terrific battering of seven weeks, Louisbourg again capitulated.

This time the British took no chances. Demolition experts drove galleries beneath the walls, packed them with explosives, and blew Louisbourg sky-high. For one hundred years the ruins lay barren and deserted.

Then, after the coal mines on Cape Breton shut down in the 1960s, the Canadian government embarked on a twenty-five-million-dollar reconstruction program. Today virtually all of old Louisbourg stands just as it stood when Louis XV was grumbling about how much it cost.


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