He was the son of Nicol Macnicol of Succoth, Argyll, and the nephew of Alexander Stewart of Invernahyle in the Strath of Appin.
MacNicol assisted the renowned Gaelic poet, Duncan Ban MacIntyre, by transcribing over 6,000 lines of the illiterate man's work.
MacNicol is also remembered for his Gaelic poem for unrequited love, entitled Mo Shùil Ad Dhèidh.
MacNicol wrote the poem as a lament for his unrequited love for Lillias Campbell, a local laird's daughter.
However, Sir Alexander made an ungallant bet with a servant which left the incensed Lillias no choice but to break off their engagement and accept the alternate proposal of the local minister.