What is the population rank of the official region of England which has the town of St Helens ? 
Metropolitan Borough of St Helens: The Metropolitan Borough of St Helens is a metropolitan borough of Merseyside, in North West England. Metropolitan Borough of St Helens:  It is named after its largest town St Helens, and covers an area which includes the settlements of Sutton, St Helens, Earlestown, Rainhill, Eccleston, Clock Face, Haydock, Billinge, Rainford and Newton-le-Willows. North West England: North West England, one of nine official regions of England, consists of the five counties of Cheshire, Cumbria, Greater Manchester, Lancashire and Merseyside. North West England:  It is the third most populated region in the United Kingdom after the South East and Greater London.
the third most populated