The name Crosthwaite, also commonly spelled Crosthwait, Crosswait and later Crosswhite is an English word meaning a clearing in the shape of a cross.  A note to visitors at St. Kentigern Church,  Keswick, Cumbria, United Kingdom states that " the church is dedicated to St. Kentigern, the first Bishop of Strathclyde and missionary to Cumberland and North Wales.  He came to this area and set up his cross in a clearing ( Thwaite ) here in the year  570 A.D.  All branches of Crosthwaite descended from the family who lived next to the most ancient  Crosthwaite Church built by St. Kentigern.

The earliest record of the Kentucky Crosthwaite, is William, who came to Pennsylvania in 1706 and reportedly set up the Philadelphia Library with Benjamin Franklin.  Pennsylvania Magazine Vol.23 page 107. 

William was co-subscriber with Benjamin Franklin  to the deed of co-partnership in the first lending library in America.

  A early land transaction  in Spotsylvania County, Virginia mentions William Crosthwait late of the province Pensilvania but now of the Parish County " aforesaid, i.e., St Mark's Parish.

 By 1738 he is listed in Orange County, Virginia.  In " The First Settlers Of Orange County, Virginia" by Ulysses P. Joyner, Jr. Gateway Press, Inc. 1987 page 114 and 115 refers to William Crostwait as owning an ordinary house on land originally purchased from Thomas Jackson.

William built his home at what became an important crossroads between Pennsylvania and Charlotte, Virginia and points east and west thereof.  This large structure, licensed as an " house of ordinary" grew into the town of Orange, Virginia.