If it helps, the regimental flag was the colour of the regiment’s PIPING colour rather than the facing colour. This signified the peacetime regional division (north, central or south) to which the regiment belonged – either red, yellow or white. The yellow saltire on the red/blue King’s Colour is something of a mystery. Some sources suggest that it was added as an honorific to certain regiments, while other sources suggest that it was added to all King’s Colours. Portuguese regiments originally consisted of a single ten-company battalion, which carried both colours. However, this became two battalions in around 1806ish and the colours were split up – the 1st Battalion getting the King’s Colour and the 2nd Battalion getting the Regimental Colour. Regiments were occasionally amalgamated into a single battalion due to losses and might therefore carry both colours together. Cacadores did not normally carry colours, but the 7th and 11th Cacadore Regiments were awarded colours as an honorific in late 1813 or early 1814. As single-battalion regiments they carried both colours in the same battalion. Cavalry regiments had one standard per squadron in the regiment. These were white for the 1st Sqn, red for the 2nd, yellow for the 3rd and light blue for the 4th squadron.
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