The surname is derived from the Gaelic word for a Norseman, but according to tradition Clan MacLachlan is descended from Niall Noigiallach, Niall of the Nine Hostages, High King of Ireland, through Ferchar of Abrothan, Prince of Aileach.
Recent research has thrown doubt on the Irish origin, postulating a wider Gaelic Society that in Argyll was isolated from the Pictish culture to the East because of difficult communication routes.
Whatever the origins there is documentary evidence that Lachlan Mor was established on the shores of Loch Fyne by the 13th century. By 1292, having acquired lands in Cowal through marriage, Archibald MacLachlan was one of the Barons whose lands were formed into the Sheriffdom of Argyll. Ewen MacLachlan rendered homage to Edward I of England in 1296, but Gillespie MacLachlan attended Robert the Bruce's first Parliament in 1309.
Only too aware of the rising influence of the Campbells of Argyll, the MacLachlans formed an alliance with them, and in 1615, Lachlan Og, the MacLachlan Chief, was with the Earl of Argyll when he moved against the MacDonalds of Islay.
In 1633, he was confirmed as Laird of MacLachlan. In 1656, Lachlan MacLachlan of that Ilk was created Justice of the Peace for Argyll by Oliver Cromwell and in 1680, Archibald, 15th Chief, received a Charter for the Barony of Strathlachlan.
The MacLachlans were Jacobite supporters and in 1715, they followed the Earl of Mar at the Battle of Sheriffmuir. In 1745 they joined Prince Charles Edward Stuart on his march into England. The following year, Lachlan, the Chief, was killed at Culloden whilst leading his Clan into battle.
The clan motto, 'Fortis et Fidus', means 'Brave and Trusty'.
The Clan MacLachlan Society was founded in 1979 and now has over 1200 members
world-wide, spread over a number of branches.
The parent society produces a bi-annual magazine, ‘Clan Lachlan’,which publishes a variety of articles of interest to Clan members .The branches all produce their own local newsletters and organise events and gatherings. MacLachlans of all spellings are welcome to join the Society, as are members of Clans Gilchrist and MacEwen.