People: Adolph Franz Friedrich Ludwig (Freiherr von) Knigge (1752–1796), German writer Rolf Peter Knigge (1951–1990), German pop singer/songwriter
Etiquette Adolph Freiherr Knigge's 1788 book On Human Relations is still often referred to as Knigge Derived from the above, any ruleset or book that concerns itself with etiquette
See also 32899 Knigge (1994 PY1), a main-belt asteroid discovered on 1994 by F. Borngen