Murdo was born in 1856, the eldest child of John MacLeod and Mary MacLeod of Baile. In 1875 the family moved to Lamerick. Murdo remained unmarried, working as a farm servant.

Murdo Mòr was a good friend of the bard Malcolm MacAskill, often accompanying him on fishing and hunting expeditions:

'S an bhios an t-aigneadh le ghad air a dhruim

'N am dha bhith faisg air na bailtean le spid

'N t-seana mhosgaid ghlagach fo n' achlais nach claoidh

B' e toileachadh fhaicinn, bhiodh tlachd air is aoibh.

 

Nam biodh n bha shùlairean ùr' aice cruinn

'Gan gleidheadh do dh' Uisdean gu cùramach grinn,

Dh'fhalbhadh e 's shiubh'leadh e uine gun sgios

Sgiathail 's an iarmailt 's e triall leis a' ghaoith

Murdo also worked as a fisherman, dealing with inclement conditions in the Sound of Harris. His friend wrote:

Cha robh duine dhèanadh iomradh

Leis mar bha iad air a tunnachadh.

Ach bha rudeiginn air Murchadh

Is na toir iomradh air càch.

 

Bha iad shios is shuas 'nan sineadh:

Bha iad thall 's a bhos a dìobhairt:

Cha robh sannt ad' air an dinneir

'S boinne tì cha robh air bòrd.