The first six Clan Chiefs are poorly represented in historical records and are included by some Clan historians and omitted by others. Buchanan of Auchmar and Guthrie Smith commence their respective numbering of Chiefs at a different person and describe a different order and number of Chiefs following Sir Walter 11th of Buchanan. In part this is due to the heir apparent not succeeding to the chiefship before he dies and chiefship passing directly from grandfather to grandchild. The following lineage reconciles Guthrie Smith and Buchanan of Auchmar and their respective numbering is in parenthesis.