The town proved its worth as a military base in the French and Indian War (the North American Theatre of the Seven Years' War) as a counter to the French fortress Louisbourg in Cape Breton.
Halifax provided the base for the Siege of Louisbourg (1758) and operated as a major naval base for the remainder of the war.
On Georges Island (Nova Scotia) in the Halifax harbour, Acadians from the expulsion were imprisoned.

On April 2, 1756, Mi'kmaq received payment from the Governor of Quebec for twelve British scalps taken at Halifax.
Acadian Pierre Gautier, son of Joseph-Nicolas Gautier, led Mi'kmaq warriors from Louisbourg on three raids against Halifax in 1757.
In each raid, Gautier took prisoners or scalps or both.
The last raid happened in September and Gautier went with four Mi’kmaq and killed and scalped two British men at the foot of Citadel Hill.
 (Pierre went on to participate in the Battle of Restigouche.)
 
By June 1757, the settlers at Lawrencetown had to be withdrawn completely from the settlement of Lawrencetown (established 1754) because the number of Native raids eventually prevented settlers from leaving their houses.
In April 1757, a band of Acadian and Mi'kmaq partisans raided a warehouse at near-by Fort Edward, killing thirteen British soldiers and, after taking what provisions they could carry, setting fire to the building.
A few days later, the same partisans also raided Fort Cumberland.
 Because of the strength of the Acadian militia and Mi'kmaq militia, British officer John Knox wrote that "In the year 1757 we were said to be Masters of the province of Nova Scotia, or Acadia, which, however, was only an imaginary possession."
 He continues to state that the situation in the province was so precarious for the British that the "troops and inhabitants" at Fort Edward, Fort Sackville and Lunenburg "could not be reputed in any other light than as prisoners."

In nearby Dartmouth, Nova Scotia, in the spring of 1759, there was another Mi'kmaq attack on Eastern Battery, in which five soldiers were killed.
In July 1759, Mi'kmaq and Acadians killed five British in Dartmouth, opposite McNabb's Island.

After the French conquered St. John's, Newfoundland in June 1762, the success galvanized both the Acadians and Natives.
They began gathering in large numbers at various points throughout the province and behaving in a confident and, according to the British, "insolent fashion".
Officials were especially alarmed when Natives concentrated close to the two principal towns in the province, Halifax and Lunenburg, where there were also large groups of Acadians.
The government organized an expulsion of 1,300 people, shipping them to Boston.
The government of Massachusetts refused the Acadians permission to land and sent them back to Halifax.

The most famous event to take place at the Great Pontack (Halifax) was on May 24, 1758, when James Wolfe, who was headquartered on Hollis Street, Halifax, threw a party at the Great Pontack prior to departing for the Siege of Louisbourg (1758).
Wolfe and his men purchased 70 bottles of Madeira wine, 50 bottles of claret and 25 bottles of brandy.
Four days later, on May 29 the invasion fleet departed.
Wolfe returned to his headquarters in Halifax and the Great Pontack before his Battle of the Plains of Abraham.
By the end of the year the Sambro Island Lighthouse was constructed at the harbour entrance to develop the port city's merchant and naval shipping.

A permanent navy base, the Halifax Naval Yard was established in 1759.
For much of this period in the early 18th century, Nova Scotia was considered a frontier posting for the British military, given the proximity to the border with French territory and potential for conflict; the local environment was also very inhospitable and many early settlers were ill-suited for the colony's wilderness on the shores of Halifax Harbour.
The original settlers, who were often discharged soldiers and sailors, left the colony for established cities such as New York and Boston or the lush plantations of the Virginias and Carolinas.
However, the new city
The town proved its worth as a military base in the French and Indian War (the North American Theatre of the Seven Years' War) as a counter to the French fortress Louisbourg in Cape Breton. Halifax provided the base for the Siege of Louisbourg (1758) and operated as a major naval base for the remainder of the war. On Georges Island (Nova Scotia) in the Halifax harbour, Acadians from the expulsion were imprisoned.
On April 2, 1756, Mi'kmaq received payment from the Governor of Quebec for twelve British scalps taken at Halifax. Acadian Pierre Gautier, son of Joseph-Nicolas Gautier, led Mi'kmaq warriors from Louisbourg on three raids against Halifax in 1757. In each raid, Gautier took prisoners or scalps or both. The last raid happened in September and Gautier went with four Mi’kmaq and killed and scalped two British men at the foot of Citadel Hill.  (Pierre went on to participate in the Battle of Restigouche.)  
By June 1757, the settlers at Lawrencetown had to be withdrawn completely from the settlement of Lawrencetown (established 1754) because the number of Native raids eventually prevented settlers from leaving their houses. In April 1757, a band of Acadian and Mi'kmaq partisans raided a warehouse at near-by Fort Edward, killing thirteen British soldiers and, after taking what provisions they could carry, setting fire to the building. A few days later, the same partisans also raided Fort Cumberland.  Because of the strength of the Acadian militia and Mi'kmaq militia, British officer John Knox wrote that "In the year 1757 we were said to be Masters of the province of Nova Scotia, or Acadia, which, however, was only an imaginary possession."  He continues to state that the situation in the province was so precarious for the British that the "troops and inhabitants" at Fort Edward, Fort Sackville and Lunenburg "could not be reputed in any other light than as prisoners."
In nearby Dartmouth, Nova Scotia, in the spring of 1759, there was another Mi'kmaq attack on Eastern Battery, in which five soldiers were killed. In July 1759, Mi'kmaq and Acadians killed five British in Dartmouth, opposite McNabb's Island.
After the French conquered St. John's, Newfoundland in June 1762, the success galvanized both the Acadians and Natives. They began gathering in large numbers at various points throughout the province and behaving in a confident and, according to the British, "insolent fashion". Officials were especially alarmed when Natives concentrated close to the two principal towns in the province, Halifax and Lunenburg, where there were also large groups of Acadians. The government organized an expulsion of 1,300 people, shipping them to Boston. The government of Massachusetts refused the Acadians permission to land and sent them back to Halifax.
The most famous event to take place at the Great Pontack (Halifax) was on May 24, 1758, when James Wolfe, who was headquartered on Hollis Street, Halifax, threw a party at the Great Pontack prior to departing for the Siege of Louisbourg (1758). Wolfe and his men purchased 70 bottles of Madeira wine, 50 bottles of claret and 25 bottles of brandy. Four days later, on May 29 the invasion fleet departed. Wolfe returned to his headquarters in Halifax and the Great Pontack before his Battle of the Plains of Abraham. By the end of the year the Sambro Island Lighthouse was constructed at the harbour entrance to develop the port city's merchant and naval shipping. 
A permanent navy base, the Halifax Naval Yard was established in 1759. For much of this period in the early 18th century, Nova Scotia was considered a frontier posting for the British military, given the proximity to the border with French territory and potential for conflict; the local environment was also very inhospitable and many early settlers were ill-suited for the colony's wilderness on the shores of Halifax Harbour. The original settlers, who were often discharged soldiers and sailors, left the colony for established cities such as New York and Boston or the lush plantations of the Virginias and Carolinas. However, the new city 
History of Halifax (former city)