I found this about the Northern Lights of Old Aberdeen

The Northern Lights of Old Aberdeen song is a traditional Scottish song written by Mary Webb [sic] for a home sick Aberdonian lass who she worked with in a hospital kitchen. Mary Webb was English and lived in London and had never been to Aberdeen, Scotland. She was born in Leamington Spa and was a concert pianist. Her fellow worker was invited to Mary's house for tea and when they were talking about Aberdeen Mary asked if that was where the Aurora Borealis, the Northern Lights, could be seen. Mary Webb composed the words to Northern Lights of Old Aberdeen to cheer up the homesick woman. Mary Webb then sent the Northern Lights of Old Aberdeen lyrics to Robert Wilson who was a Scottish tenor. He sang it at the Albert Hall and the Northern Lights of Old Aberdeen song grew in popularity. Mary Webb came to Aberdeen and performed the Northern Lights of Old Aberdeen at the Tivoli Theatre.

Mary Webb died at Charing Cross Hospital in London aged 88 years. By co-incidence the BBC were making a documentary about her and found that her body had remained unclaimed for three weeks. Her ashes were scattered in the grounds of Kaimhill Crematorium. Her John Broadwood piano on which she composed the Northern Lights of Old Aberdeen was saved by broadcaster, author and journalist Jack Webster who was working for BBC Scotland and presented to Aberdeen Council. It stayed in storage in Kittybrewster before being put on display in 2009 and unveiled by Lord Provost Peter Stephen, Duncan Hendry the head of HMT (His Majesty's Theatre) and Jack Webster. The piano can now be seen in the Mary Garden room of the Aberdeen Music Hall. The documentary about Mary Webb was shown on BBC Scotland in 1989.

Source: http://www.aboutaberdeen.com/northern-lights-of-old-aberdeen.php

I was surprised it was composed so recently. I was born in Aberdeen but have not lived there since the age of eight. I moved away in early 1953 and even so the song has somehow been part of the background to my life. Maybe it is the very singable melody which also helped to catch on in the first place.