"BOSWELL'S (ST.), or LESSUDDEN, a parish containing a post-office village of its own name, on the north border of Roxburghshire. It is bounded on the north by Berwickshire, and on other sides by the parishes of Maxton, Ancrum, Bowden, and Melrose. Its length north-eastward is 3 miles; and its breadth is about 1½ mile. The Tweed, flowing between bold, beautiful, well-wooded banks, forms the boundary with Berwickshire ... Population of the parish of St Boswell's in 1831, 701; in 1861, 865."
"The VILLAGE OF ST BOSWELL's or LESSUDDEN stands on the east side of the parish, nearly opposite Dryburgh Abbey, 4 miles south-east of Melrose, and 10 west-south-west of Kelso. The original village of St Boswell's stood about ¾ of a mile south-east of this, but has completely disappeared. It derives its name from St Boisel, who was the preceptor of St Cuthbert, and is supposed to have founded the church. The present village generally bears the name of Lessudden, and may have originally been called Lis-Aidan, which means the residence of Aidan, or perhaps Lessedwin - as it is in the old chartularies - that is, the manor-place of Edwin."
From the Imperial Gazetteer of Scotland, edited by John Marius Wilson, 1868.