The Sovereign Military Order of St. John of Jerusalem, Rhodes and Malta was founded in 1099 and Chapters were established throughout Europe. This historical Badge evidently belonged to a Master of the Order in the mid 17th Century. They were individually commissioned and so the few surviving examples are all slightly different

Cf. S. Patterson, Royal Insignia, Merrell, 1996, p. 30-32 for a similar early 17th century example