##>> This is considered by many to be the archetypal dance created to an already well known tune, in this case The Lewis Bridal Song.
The words of the song Mairi’s Wedding were added by Sir Hugh S Robertson, founder of the Glasgow Orpheus Choir. There is also a Gaelic song version with words by John Bannerman.
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John Roderick (Johnny) Bannerman (1865-1938) from South Uist wrote the original Gaelic words of the song in 1935, for 1934 National Mod gold medalist singer Mary C. MacNiven of Portnahaven, Islay. Mary’s actual wedding (to sea captain John Campbell) didn’t take place until 1941. Sir Hugh S. Roberton (1874-1952), founder of the acclaimed Glasgow Orpheus Choir and a leading choir master of the time, came up with the well-known English lyrics – only very loosely related to Bannerman’s Gaelic ones – in 1936. Mary had been born in 1905 and passed away on 25 March 1997, at age 91.
(See Mary's obituary.)
On dance programmes, the »Mairi« in the title of the dance is often spelled »Mhairi«. This does look vaguely more »Gaelic« but would have to be pronounced »VAA-ri«. It would also be grammatically incorrect.
As a common variant, some dancers pass by the right between the diagonal half-reels of four (contrary to the express wishes of the author, James Cosh). This variant has the nickname »Mairi’s Divorce«, which is a bit disrespectful as the real Mary never divorced. In 1998 Angus Henry somewhat jokingly »devised« and published the right-shoulder variant using that nickname.
Since the pass only involves the first couple, they can choose the shoulder as they wish at each pass without disturbing the rest of the set.