The 1st Canadian Division's attack on the Hitler Line started ay 0600 hours on 23 May with two brigades up - 2nd Brigade right and 3rd Brigade left. The 1st Brigade relieved the second later in the day with the 48th Highlanders and supporting tanks in the lead. The Hastings and Prince Edward Regiment followed and relieved the 48th Highlanders in their attack on Point 106. The Hitler line was breached in the early evening as the 5th Armoured Division prepared to break through to the Melfa.
The 23rd of May was the worst single day in terms of casualties for the Canadian Army in the Italian Campaign. Eight hundred and ninety (890) Canadians were killed or wounded. The 2nd Brigade alone suffered 543 casualties, and supporting British armour lost 44 tanks. As these events occurred, the Allies were finally breaking out of the Anzio beachhead, threatening to cut the Germans off from the rear, making exploitation of the Hitler Line penetration a priority.
The biggest task for the Engineers on the Hitler Line was breaching minefields. Besides being covered by fire and defended by dug-in tank turrets and pillboxes, the minefield was over 200 feet deep with heavy barbed wire on either side. It included Italian box mines, mostly surface laid. Each brigade went into battle with a supporting field company. The Sappers started during the night of 22/23 May, gapping minefields even before the assaulting troops were in position. This is where we find Sgt Shiers.
On 23 May 1944, 1 Canadian Infantry Brigade was to attack an area in the Adolph Hitler Line. F.91434 Sergeant Hugh Winslow Shiers was in charge of a minefield gapping party in the support of the Hastings and Prince Edward Regiment of that brigade. In support of this attack was a squadron of tanks from 142 Regiment, Royal Armoured Corps. On the evening of 22 May 1944 Sergeant Shiers twice led a detector team forward clearing lines [mines ?] from roads and tracks leading to Pontecorvo. Although subjected to heavy mortar fire and continuous sniping he repeatedly returned to his task of clearing mines in the face of severe enemy opposition. Although daylight had broken before his task was completed, he continued his efforts in the face of increasing enemy fire and successfully completed his task. As a direct result of his efforts, the British tanks were free to use these tracks in close support of the infantry attack. He displayed outstanding resolute coolness and courage in the face of enemy opposition. His fearless determination and devotion to duty was a splendid example to all ranks. (See MM awarded to Acting Corporal George Edgar Parker, 22 June 1944). NOTE: About September 1943, Lieutenant-Colonel G. Walsh (1 Canadian Division) recommended Lance-Sergeant Shiers for the Canada Medal (an award subsequently bestowed on no person). The document text is transcribed for the historical record: This Non-Commissioned Officer has many times neutralized booby traps set by the enemy. In one particular case, an enemy ammunition lorry was found and was suspected of booby traps. It was not possible to use the normal method of moving the lorry by using a long rope as it would have held up the advance, and would have been a source of danger to nearby troops. It had to be removed, and Lance-Sergeant Shiers, realizing this, personally neutralized the booby traps which were found, and then arranged for the clearing of the vehicle at great personal risk.