Following Dr. Joseph Jackson Howard, Miscellanea Genealogica et Heraldica, Vol. III,
Greisbrook Family Notes
See especially Robert Sewell's overview and genealogy of the Grazebrook family. A summary in PDF format is also available.
His primary source is:
Dr. Joseph Jackson Howard, Miscellanea Genealogica et Heraldica, Volume III, Third Series (London: Mitchell and Hughes, 1900), available at Archive.org. [Read relevant excerpts.]
Eben W. Graves also cites this book in his Descendants of Henry Sewall (see Sewall).
Dr. Howard traced the family back to Bartholomew de Gresebrok, who lived circa 1200. He was the one who acquired what became known as Gresbrok Hall from Robert de Grendon, as well as an estate in Shenston, Warwickshire, England. He believed the pedigree could be take back further, to about 1065.
Many of the primary documents referenced in his work are available in the Staffordshire Historical Collections, online at british-history.ac.uk.
"Greisbrooke of Shenstone" is also treated in "The Heraldic Visitations of Staffordshire Made by Sir Richard St. George, Norroy, in 1614, and by Sir William Dugdale, Norroy, in the Years 1663 and 1664" in Collections for a History of Staffordshire, edited by The William Salt Archaeological Society [and Henry Sydney Grazebrook] (Mitchell and Hughes, 1885) (beginning on page 156). This work is available at Google Books. [Read excepted section.]
Alternate spellings: Gresbroc, Gresebroc, Gresebrok, Greisbrook, Gresbrook, Graysbrook, Greysbrooke, Grazebrook