According to Pooley Sword:
Because British cavalry officers always led their men from the front, the officer’s charger was the most imposing horse on the battlefield – a larger, more powerful animal than the ordinary trooper’s horse. This called for a weapon of comparable dimensions, and the Household Cavalry Officer’s sword is the longest in the British Army.
This 1892 pattern sword is carried on state occasions by officers of the Life Guards and the Blues & Royals.
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