Survivors and relatives of those who fought in the Battle of the Atlantic boarded HMCS Sackville in Halifax harbour to commemorate those who lost their lives at sea.

The battle, which claimed numerous Canadian lives, was a pivotal campaign in ending the Second World War.

For six years Canadian forces transported vital supplies across the Atlantic to the Allies fighting in Europe.

"We were there to make sure the convoy was protected above everything," Second World War Veteran Bill Irving told CTV Halifax on Sunday.

Irving says that he still feels lucky to have survived the battle.

"A lot of ships in the same job didn't go back," he said. "We were close to the Shawinigan and they lost everyone."

The battle claimed the lives of 16,029 merchant mariners. With one in 10 marines killed in the Battle of the Atlantic, it was the highest percentage of deaths for any military branch.

More than a dozen veterans from the battle gathered to pay their respects on Sunday.

"To me, it's just a case of all the boys that didn't come back ... army, navy, and the air force," Eric McLeod said.

As well as remembering those who lost their lives at sea, the sombre service also honoured the sailors and soldiers who died during the past year.

The ashes of sixteen servicemen were laid to rest at sea.

Margaret Lillington told CTV Halifax that while her husband, Samuel, wouldn't talk about his time in the war, he made it clear to his family that he wanted to be buried at sea.

"He said, 'I hope they take me out the Sackville,' so he's getting his wish today," Lillington said.

Several present-day military personnel were also at the ceremony at sea.

"It's poignant I think as well because we have Canadian forces engaged in action today," Cmdr. Dean McFadden said.

He said that as the number of survivors dwindles each year, it becomes more important to remember their sacrifices and pass their legacies on to future generations.

The longest campaign

The battle, which lasted from September 3, 1939 to May 7, 1945, was the longest campaign of Second World War and one of the most important.

The Battle of the Atlantic was primarily fought between Canadian merchant marine and navy ships and German U-boat submarines.

In July 1940, U-boats started attacking merchant ships bound for Britain as the Battle for Britain had begun, with Nazi bombers striking targets in England.

Keeping Britain supplied left 3,600 Canadians dead -- making it the most dangerous duty our nation had during the Second World War.

By April 1942, more than 198 vessels had been sunk by U-boats, including a ferry that ran between Newfoundland and Cape Breton. The subs also laid mines near the harbours of St. John's and Halifax.

But still the ships set out for Britain, helping that nation defend itself.

By 1943, the Allies had developed effective strategies for counterattacking the U-boats. The ships went on with their work of transporting supplies and troops.

While the U-boat threat was diminished after 1943, the cat-and-mouse game continued until Germany surrendered on May 7, 1945, leading to V-E Day being declared the next day.

People in St. John's got to see a captured U-boat in their port after V-E Day in 1945.

With a report from CTV's Tracy Prysiazniuk