I have been researching the Mosby name in England for about a year. As with nearly everyone of Mosby descent my family originate from the Garforth, Kippax, Swillington, Micklefield and Allerton Bywater area of Yorkshire.
One of the people to reply earlier, Shawn Donat, must I am sure be a relation of Rhonda Donat who I have recently been working with to try and link our Mosby lines.
The Donat family have done extensive research into the Mosby name in England. The vast majority if not all Mosbys in the UK can be linked back to George Morrisbe born York (1639/40) but who settled in the Garforth/Kippax area of Yorkshire.
The Donats have an excellent site on rootsweb which sets out the descendants of George Morrisbe.