A lady in Henderson found in Gilford county, NC has a book in German, getting it translated traced back to Germany. Family originally from Norway. Osgod Clappa.
This parish in all probability received its appellation from one of its proprietors. Osgod Clappa was the name of the Danish lord, at whose daughter's marriage-feast, in Lambeth, Hardicanute died (fn. 1) . In Doomsday book, however, this place is called Clopeham.
[Source: 'Clapham', The Environs of London: volume 1: County of Surrey (1792), pp. 159-169. URL: http://www.british-history.ac.uk/report.aspx?compid=45376 Date accessed: 19 February 2009.]
See also: http://www.houseofnames.com/xq/asp.fc/qx/clapton-family-crest.htm