The "Brian Boru" harp, now at Trinity College, Dublin, bears the coat of arms of the O'Neills but although there are many theories about its ownership through the centuries, none can be substantiated, with no verifiable evidence remaining to indicate the harp's original owner, or subsequent owners over the next two to three hundred years until it passed to Henry McMahon, of Co. Clare, and finally to The Rt. Hon. William Conyngham, who presented it to Trinity College in Dublin in 1760.
Throughout its history the harp was in the possession of of many people some of which were kings.
The Trinity College harp is currently displayed in the long room at Trinity College Dublin. It is an early Irish harp or wire strung cláirseach. It is dated to the 14th or 15th century and along with the Queen Mary Harp and the Lamont Harp, is one of the only three surviving medieval Gaelic harps.
Related to the Trinity College Harp, there are two greatest medieval harps of Scotland, the "Queen Mary" and the "Lamont" harps. Both kept in the National Museum of Antiquities in Edinburgh.
Both “low headed” Celtic harps date from the 15th Century, and each is from a single piece of wood, possibly hornbeam, hollowed out from the back. The Lamont harp, which is unadorned, is the larger harp at 37 ½ “, with 32 wire strings.The Queen Mary is ornately carved with intricate designs, including griffins, a lion, a dragon and a unicorn, almost 31” high, with 30 wire strings.
A right-facing image was registered as a trade mark for Guinness in 1862, and was first used on their labels in 1876.
All three surviving Gaelic harps (the others are the Lamont Harp and the Queen Mary Harp) are considered to have been made in Argyll in South-West Scotland sometime in the 14th-15th century.