Gang in Northern Chicago using the same name as a medieval order
The Knights Templar are a gang in northern Chicago that claims a lineage towards a French military order from the 12th century. Whether that connection is real or not remains a matter of debate, but gang members always bare tattoos of the Templar cross and are known for carrying swords and other medieval weapons to gun fights with surprising levels of success.
They are led by Grand Master Clairvaux, and are loosely allied with the North Side Gang.
Supernatural Connections
There are no known supernatural connections held by the Knights Templar, though most in the supernatural community believe there has to be something both because of the name they carry and the fact that they appear to be able to succeed while bringing swords to gunfights which would not make sense otherwise.