Greenlaw was county town of Berwickshire between 1698 and 1903. A number of buildings reflected this status, and most of these can still be seen today.

The Earls of Marchmont, members of the Hume family, were instrumental in Greenlaw gaining county town status for Greenlaw, and they also paid for a number of buildings at their own expense. In the late seventeenth and early eighteenth centuries, the 3rd Earl of Marchmont had the jail and courthouse constructed, and in 1829, the Town Hall and a new market cross were built at the expense of Sir William Purves Hume Campbell, successor to the Earls of Marchmont.