The MacKintoshes (Mac an Toisich) are paternally an offshoot of the Clan MacDuff of Fife, whose chiefs, the earls of Fife, held vast territory in Moray during the thirteenth century. Rothiemurchus, the earliest known territory of the Mackintoshes, was surrounded by this territory. In 1291, Angus, sixth chief of the MacKintoshes, married Eva, daughter and only child of Dougal Dall, sixth chief of the Clan Chattan. The Clan Chattan line stretched back to the first chief, Gillechattan Mor, heir of the co-arbs of the abbey of Kilchattan on the Isle of Bute, the special abbey of the Cineal Loairn. The line of this Gillechattan Mor, whose name means "great servant of St. Cattan" (the patron saint of the Abbey of Kilchattan) acquired land in Lochaber and Badenoch, probably by Pictish succession. This may explain the use of the wildcat as the heraldic beast of the Clan Chattan, informally referred to as the Clan of the Cats: St. Cattan’s name means "little cat," and the Northern Picts had an ancient totemistic connection to the cat (hence the name of the province of Caithness in northern Scotland—see under "Sutherland" in Chapter X). As for the MacKintoshes, since no surname was associated with the Clan Chattan chiefship in these virtually pre-surname days in Scotland, the new line of MacKintoshes kept their name, but continued as captains of the Clan Chattan.

The Clann Fhionnlaigh or Farquharsons (Mac Fhearchair) of Invercauld in Aberdeenshire are descended from the Shaws of Rothiemurchus, cadets of the MacKintoshes. They inherited Invercauld from the MacHardys.

The MacPhersons (Mac an Phearsoin) descend from Ewan Ban, son of Muriach, "Macgilliechattan Clearach," Celtic Prior (or "Parson") of Kingussie, and fourth chief of the Clan Chattan. With the passing of the chiefship to the MacKintoshes through Eva, daughter of the sixth chief, the MacPherson chiefs represented the male-heir of the Clann Chattan, and thus disputed, with the MacKintoshes, the high-chiefship of the Clan Chattan, and with the Clann Dhai or Davidsons, the leadership of the right wing (the position of honor) of the Clan Chattan’s 2000-man army.

The Davidsons (Mac Dhaibhidh) descended from David Dhu, another son of Muriach, ancestor of the MacPhersons. In order to hamper the unity of the powerful Clan Chattan, the early Stewart kings played off the MacPhersons against the Davidsons by formenting the continuance of their dispute. This action led to the famous Battle of the Clans at Perth in 1396, a "legal battle" before the king, contested to the death between a limited number of clansmen of the MacPhersons and the Clan Dhai (the identity of the Davidsons as the latter party, although likely, has not been proven absolutely).