Queen Elizabeth II recognized many individuals with honors of the Most Excellent Order of the British Empire. During her legendary reign as Queen, she knighted a number of popular musicians.

Here’s a brief explainer on the various levels of the Most Excellent Order of the British Empire. Per the U.K.’s official Honours System website, the following are the five title distinctions in order of importance the British Monarchy can bestow upon individuals for their non-combative contributions to the U.K.:

Member of the Order of the British Empire (MBE): “Achievement or service in and to the community which is outstanding in its field and has delivered sustained and real impact which stands out as an example to others.”

Officer of the Order of the British Empire (OBE): “Distinguished regional or county-wide role in any field, through achievement or service to the community including notable practitioners known nationally.”

Commander of the British Empire (CBE): “A prominent national role of a lesser degree, a conspicuous leading role in regional affairs through achievement or service to the community, or a highly distinguished, innovative contribution in his or her area of activity.”

Damehood/Knighthood (DBE/KBE): “A pre-eminent contribution in any field of activity (usually, but not exclusively, at national level), or in a capacity which will be recognized by peer groups as inspirational and significant nationally and demonstrates sustained commitment.”

Dame/Knight Grand Cross (GBE): “Grand Cross is the highest class in many of the Orders.”

With those definitions in mind, here are 13 iconic musicians knighted by Queen Elizabeth II.