Also spelled "sergeants" and the root of the modern term for non-commissioned officers in the army. In Medieval times a sergeant was also know as a man-at-arms or, in simpler terms, a knight who was not knighted. They were commoners who had proven their ability to fight like a knight and were equipped as such by their masters. These men were the servants of a knight or higher ranking noble and were part of his "fellowship ." Serjeants were equipped more or less as knights, albeit that their equipment was inferior to that of their master, usually hand-me-down armor and weapons and less splendid horses. Becoming a serjeant was one way a commoner cold get a leg up into the ruling class. Long distinguished service might result in a knighthood, or at least a small fief of one's own.</p>
Cheers mate but that doesnt answer my question i believe it may have been a battle honour to let the light infantry call their serjeants spelt with a j and not g
Further info here <h2>Sergeant or Serjeant</h2> The spelling serjeant is sometimes seen. This was in fact the official spelling, even during and after World War I – though interestingly not in the Royal Air Force – andappeared in such publications as King's Regulations and the Pay Warrant, which defined the various ranks. In common usage themodern spelling sergeant was already more usual, as for instance in the volumes of the Official History which began toappear in the 1920s. Serjeant-at-Arms is a title still held by members of the securitystaff in the Houses of Parliament.</p> <a name="wp-Historical_Ranks"></a></p><h2>Historical Ranks</h2><dl><dd>Serjeant-Major: equivalent to the current Regimental SergeantMajor, a warrant officer class 1</dd><dd>Company Serjeant-Major: now an appointment of Warrant Officer class 2</dd><dd>Quartermaster Serjeant: can now be a Regimental Quartermaster Sergeant(Warrant Officer class 2) or a CompanyQuartermaster Sergeant (Staff Sergeant)</dd><dd>Colour Serjeant: gave way to CSM/QMS over years prior to World War I althoughcolour sergeant exists today in the Royal Marines, equivalent to a staff sergeant in thearmy, and is still used to refer to all staff sergeants in infantry regiments</dd><dd>Lance-Serjeant: appointment originally given to corporals acting in the rank of sergeant, discontinued in 1946 exceptin the Foot Guards and some cadet units</dd><dd>Second Corporal: ordnance rank until 1920, equivalent to lance-corporal but asubstantive instead of an acting rank</dd><dd>Chosen Man: became lance corporal in early 1800s</dd></dl>From http://www.answers.com/topic/british-army-enlisted-rank-insignia