The Druze
The community calls itself Muwahhidun, 'those who affirm the oneness of God' — the name 'Druze' actually derives from a historical figure their own religious texts explicitly denounce and reject, making the community's common external name a rejected association rather than a chosen one.
Philip K. Hitti, The Origins of the Druze People and Religion (1928), pp. 12, 33, 53–54: the name comes from ad-Darazī, whom Hamza ibn ʿAlī denounced in the epistle al-Ghāya wa-l-Naṣīḥa, while the community calls itself Muwaḥḥidūn
A close-knit Middle Eastern religious community with roots in eleventh-century Islamic esotericism, closed to new converts for nearly a thousand years.