The High Sheriff of Hertfordshire was an ancient Sheriff title originating in the time of the Angles, not long after the foundation of the Kingdom of England, which was in existence for around a thousand years.
[1] The High Shrievalties are the oldest secular titles under the Crown in England and Wales, their purpose being to represent the monarch at a local level, historically in the shires.
The office was a powerful position in earlier times, as sheriffs were responsible for the maintenance of law and order and various other roles.
It was only in 1908 under Edward VII that the Lord Lieutenant became more senior than the High Sheriff.
Anno 9 Elizabeth (ie 1566 or 1567): This County was severed from that of Essex, and found Sheriffs by themselves.