Royal Canadian Engineers formation patch

At the start of the Second World War, it was felt that colourful unit and formation insignia would be too easily seen, and a very austere set of insignia was designed for the new Battle Dress uniform, consisting solely of rank badges and drab worsted Slip-on Shoulder Titles. In 1941, however, the trend was reversed, and a new system of Formation Patches, based on the battle patches of the First World War, was introduced. However, the use of lettered unit titles (at first won as Slip-on Shoulder Titles and later, as more colourful designs worn directly above the divisional patches) was also introduced - a privilege previously extended only to the Brigade of Guards in England, and in the Canadian Army to just four units: Governor General's Foot Guards, Canadian Grenadier Guards, Princess Patricia's Canadian Light Infantry and the Canadian Provost Corps.

The new formation patches were made from three materials mainly; felt and wool being most common, and canvas patches were adopted in the late war period as an economy measure.

Members of various corps serving in support units originally wore formation patches with letters added directly to the patch (or in some cases a plain coloured shape, such as the Royal Canadian Army Medical Corps (RCAMC))

The hexagonal patch of the Canadian Army Pacific Force applied overtop of the formation patch indicated a volunteer for the CAPF.

When 1st Canadian Corps was formed, it was not anticipated that a second corps would be raised; Formation Patches for units of some arms and services were thus rendered in the colours of their respective arm or service (ie emerald green for the Canadian Dental Corps, blue for the Royal Canadian Engineers, etc.) rather than in red. When II Canadian Corps was raised, and a blue diamond approved as its formation patch, some of the patches worn by I Canadian Corps units had to be changed from arm of service colour to the red of I Canadian Corps.