[1] He was elected mayor in the waning days of the reign of Henry III, while the heir apparent was away on a crusade in the Holy Land.
At the time of his election, there was an ongoing rivalry between the common citizens of London and the city's aldermen.
[2] During his term, Hervey signed charters for the various crafts, in effect creating an early form of trade unions.
After his term as mayor was ended, Hervey was succeeded by Henry le Walleis.
Walleis, along with his political ally (and eventual successor) Gregory de Rokesley, nullified the charters.