Fa'side Castle acquired its name from the Fawside family who acquired the site in the late fourteenth century. The fortification itself is older though - the land was granted to Saer de Quincy, Earl of Winchester in 1189 and, on his death, to his son Roger who later granted to his own son-in-law, Alan la Zouche of Ashby. One of these individuals built the original castle; almost certainly as a fortified tower supported by various service buildings. He was still owner in 1288 when the castle was attacked by Sir William Douglas and later at the start of the first War of Scottish Independence; as English magnates the family supported Edward I and according Fa'side Castle was one of the many castles seized by Robert the Bruce after his 1306 rebellion and coronation.
Bruce granted the castle to the Seton family but they sold it to the Fawsides in 1371 who commenced a major rebuilding programme and constructed the first elements of what remains visible today. They were still the owners during the War of the Rough Wooing when, in 1547, a large Scottish army intercepted an English invasion under Edward Seymour, Duke of Somerset in direct vicinity of the castle. The Battle of Pinkie was a tactical victory for the English who burnt the castle in the wake of their victory.
Fa'side was clearly rebuilt soon after the battle for Mary, Queen of Scots stayed at the castle on 14 June 1567 before departing the following day for the Battle of Carberry Hill. Further modifications were made later in the sixteenth century with the Tower House being rebuilt into a L-plan configuration but it was sold to an Edinburgh merchant in 1631 passing out of the Fawside family. Over the subsequent centuries it was allowed to fall into ruin until purchased and restored in the mid-1970s. Today it is a private hotel/bed and breakfast.