Tanistry

Tanistry was a system of inheritance practised by the Gaelic nobilities of Ireland, the Isle of Man, and parts of modern Scotland. It was distinctive in having an elected heir known as the tanist, chosen from among eligible kinsmen rather than fixed by birth order, and the system was used to select the Chiefs of the Name and the rulers of the various Gaelic kingdoms in Ireland and in Scotland. This description is adapted from Wikipedia contributors under CC BY-SA 4.0; changes were made. https://creativecommons.org/licenses/by-sa/4.0/