The clan system is closely bound up with Scottish heraldry. The best definition of a clan provided by a heraldic authority is contained in Nisbet’s “System of Heraldry”, published in 1722: – social group consisting of an aggregate of distinct erected families actually descended, or accepting themselves as descendants of a common ancestor, and which has been received by the Sovereign through its Supreme Officer of Honour, the Lord Lyon, as an honourable community whereof all of the members on establishing right to, or receiving fresh grants of, personal hereditary nobility will be awarded arms as determinate or indeterminate cadets both as may be of the chief family of the clan.
A clan is therefore a community which is both distinguished by heraldry and recognised by the Sovereign. At the head of this honourable community is the chief. He is the only person entitled to display the undifferenced shield of Arms, ie without any marks of dependency upon any other noble house.
Chiefship is a title of honour and dignity within the nobility of Scotland. Any claimant to such a title must establish, to the satisfaction of the Lord Lyon representing the Sovereign, that he or she is entitled to the undifferenced arms of the community over which they seek to preside. It is the determining of chiefship which is among the Lyon Court’s central work.
Many of the cases which have come before the Lyon Court in the last 50 years have related to the chiefships of clans. There are now about 140 clans that have chiefs recognised by the Lord Lyon.
A clan or family. which has a recognised chief or head confers noble status on the clan or family which gives it a legally recognised status and a corporate identity. A family or name group which has no recognised chief has no official position under the law of Scotland.