The Honourable Society of Cymmrodorion (Welsh: Anrhydeddus Gymdeithas y Cymmrodorion), often called simply the Cymmrodorion, is a London-based Welsh learned society, with membership open to all. It was first established in 1751 as a social, cultural, literary and philanthropic institution. It fell into abeyance between 1787 and 1820, and again between 1843 and 1873. In its second and third incarnations its interests have been predominantly cultural and antiquarian. The present society claims continuity from that founded in 1751, although the three successive societies have in fact been slightly different in character and aims.