What is the origin ethnicity of the surname Clark?

Throughout the United Kingdom, the Word and the profession of "clerk" is typically pronounced as "clark". This common honorarium is a holdover from times long past, when this proud and noble English surname became associated with those who concerned themselves with matters of scholarly importance, religious orders, or secretarial tasks. The Clark ancestral home is believed to be in Northumberland, where they'd held a family seat- even before the Norman Conquest of 1066 A.D.

Family motto: "Fortitude!"