A successor to the 1898 work "The Magna Charta Barons and Their American Descendants," the pedigrees herein are of the members of the Order of Runnemede in 1915--in effect, a second "yearbook" of the Order. Since pedigrees were dropped and added as the membership of the Order changed, this work stands by itself and does not supersede the 1898 volume. Nearly 200 pages are devoted to pedigrees of the members, which are grouped under the following names: Abbott, Allyn, Aston, Bernard, Bevan, Booth, Brooke, Bruen, Bulkeley, Byrd, Cadwalader, Calvert, Carter, Chauncey, Chichester, Claiborne, Claypool, Clayton, Daubeney, Digges, Drake, Dundas, Evans, Fauntleroy, Fenwick, Fleete, Foulke, Gordon, Gorsuch, Haynes, Henry, Humfrey, Irvine, Lambert, Lawrence, Leete, Lindsay, Lloyd, Lyman, Lynde, MacGehee, McIntosh, Montgomery, Norton, O'Carroll, Owen, Reade, Rose, Saltonstall, Scott, Sherman, Skipwith, Spotswood, Stewart, Sullivan, Throckmorton, Warren, Washington, West, Wetherill, Whiting, Wilkinson, Williams, Willis, Willoughby, Winthrop, Witherspoon, Woodhull, and Wyatt.

As the author emphasizes at the beginning of this work, "this is a book of the genealogies of the most prominent of the English Barons who procured the great Charter of Liberty from King John rather than an essay on the Magna Charta itself, ... "