The D-Day invasion of July 4, 1944 was only the beginning.

After taking the Normandy beaches of Utah, Omaha, Gold, Juno and Sword, the Allies had a long road ahead of them which would take them through France, Belgium and Holland, and finally, at the end of the war in 1945, into Germany itself.

But before they could even set out onto that road, the Allies first had to get through the hilly countryside of Normandy, which was held by determined and highly-trained troops Germany had fielded.

Canadians coming off Juno beach faced some of the most fearsome German divisions, including the 12th SS-Panzer, which was comprised of fanatical Hitler youth, teenagers whose indoctrination led them to believe they were Hitler’s Aryan supermen.

It would take the Allies two months, from July 4 to Aug. 21, ending with the Falaise Gap and great numbers of casualties, to push through the German defences.

Those defences are what Canadian historian and author Mark Zuehlke describes in the newest book in his Canadian Battle Series, Breakout From Juno: First Canadian Army and the Normandy Campaign, July 4 – August 21, 1944, as “the greatest cataclysm of combat on the western European front during all of World War II.”

In that cataclysm, Zuehlke said, those two months, the crux of the Normandy Campaign, became more costly than the D-Day invasion itself.

In what is the first major account of Canada’s role during this period of the war, Breakout From Juno is a challenging and difficult book, as it reflects in extensive detail what was a complex two months of the war.

But that doesn’t mean this is a poorly written or researched book. Not at all. It is excellent and on par with Zuehlke’s other Canadian Battle Series books which strive to present the war through the eyes of the individuals who were there.

But the challenge for both author and reader is twofold: one, the months of July and August following D-Day are largely unknown, overshadowed by D-Day itself and two, the battles were unrelenting and chaotic, often involving all three Canadian divisions at one time, making it difficult for authors and historians to do anything but summarize that period.

“Those two months, they were really pivotal, because up to the point when they go into action on July 4, the Germans basically sealed off Normandy at the actual bridgehead, which is not that big at that point, only about six or seven miles off the beach and this thin band is jammed with people,” Zuehlke said.

From that space, the Canadians pushed forward, attacking the German defences with battles, chaos and causalities growing with each step.

“That even surprised me; the intensity and brutality of the fighting is just incredible. It doesn’t end. There’s no pause. It’s just day after day after day. Every time they win there’s another objective because the Germans just keep falling back into ever-stronger positions,” he said.

From the D-Day storming of Juno Beach through to the end of the Normandy Campaign, there were 18,444 Canadian casaulties, and of those, 5,021 men died.

During each battle, German defenders kept looking to take advantage of an opportunity to break out and push the Allies back into the sea. And the best route to do that was straight through the Canadians to Juno Beach, which Zuehlke said was a pivotal weak point.

If they could reach Juno Beach, the Germans could then cut off and clear up the British before going after the Americans, who were at a distance from the city of Caen.

“If we had been defeated in the big offensive Operation Totalize, if the Germans had been better prepared and had not been taken by surprise and had defeated us, it is conceivable they could have counterattacked with their armour and that’s what they were looking for, a hole they could punch several divisions through,” he said. “If they were ever able to have gotten back to the beach, they could have probably rolled up the invasion.”

The sheer fear of that happening kept the Allies on the attack no matter what the cost. Throughout July and August 1942, that meant the infantry had to keep moving, even though they faced unimaginable hardships.

“They’re exhausted, sick and dirty and it’s amazing, the only thing keeping them going is sheer grit,” Zuehlke said.

Breakout From Juno: First Canadian Army and the Normandy Campaign, July 4 – August 21, 1944, published by Douglas & McIntyre, sells for $36.95.