Hugh MacDiarmid is the pen name of Christopher Murray Grieve (11 August 1892 – 9 September 1978), a significant Scottish poet of the 20th century. He was instrumental in creating a Scottish version of modernism and was a leading light in the Scottish Renaissance of the 20th century. Unusually for a first generation modernist, he was a communist; unusually for a communist, however, he was a committed Scottish nationalist. He wrote both in English and in literary Scots (often referred to as Lallans).
Above taken from Wikipedia.org