When the Macintosh learned of this he called the constituent clans of the Old Clan Chattan together -- primarily the Clann Mac an Tòisich, the Clann Mhuirich and the Clann Dhai. Although this force was superior to that of the Camerons, a dispute arose among the Clan Chattan chiefs. As captain of the Clan Chattan, the Mackintosh was entitled to command the centre of the army. But a difference arose between Kenneth MacVuirich and the chief of the Clann Dhai of Invernahavon. Each claimed the right to command the right wing of the Clan Chattan force. Kenneth demanded this position as the rightful chief of the old Clan Chattan, since the Davidsons were only a branch; but Invernahavon contended that right for his clan because the battle would be waged on their land where the River Truim enters the River Spey.
The Macintosh decided against Kenneth's claim which was a most imprudent award because the Clann Mhuirich exceeded both the Mackintoshes and Davidsons in numbers. The Clann Mhuirich were so offended by this decision that they withdrew from the field, and became, for a time, spectators of the action.
The battle soon commenced, and was fought with great obstinacy. Many of the Mackintoshes, and almost all the Davidsons, were cut down by the superior number of the Camerons. The Clann Mhuirich seeing their friends and neighbours almost overpowered, could no longer restrain themselves, and friendship got the better of their wounded pride. At this perilous crisis, they rushed in upon the Camerons, who, from exhaustion and the losses they had sustained, were quickly overcome. The few that escaped were pursued from Invernahavon down the shores of Loch Ericht and Charles MacGilony was one of the last to fall, transfixed by an arrow shot by Maclan Ceann-Dubh, one of the Macvuirich archers, at the very moment that MacIan was killed by MacGillony's last arrow. Carn Mhic Ill' Onfhaidh, MacGillony's cairn, still marks the spot on Loch Ericht-side where the Lochaber chief died. But there is another story that says that he was killed on a hill in Glen Banchor, not far from Invernahavon which has long been called Torr-Thearlaich or Charles'-hill.
The outcome of the battle wasn't the end of the story. The men of Clann Dhai were almost annihilated and the survivors held Clann Mhuirich responsible. This resentment led to much recrimination and fighting during the following decade.