[1] The title takes its name after the market town of Horsham in West Sussex.
Horsham was one of the thirteen new post-English Reformation bishoprics and dioceses proposed by King Henry VIII in an ecclesiastical revision proposal written in the king's own handwriting.
[2] The subsequent reallocation of former monastic incomes allowed for the eventual creation of only six of these thirteen dioceses.
When new sees (both suffragan and diocesan) were established by the Church of England in the 20th century, the proposed Tudor dioceses which had not come into being were considered as episcopal titles.
[4] The bishop oversees the archdeaconries of Chichester & Horsham.