George Fraser Black states that in 1426, Blakadir de Eodem (of that Ilk) held the lands in the earldom of March.

In 1518 the family lost their Border lands by the forced marriages of the two heiresses of Robert Blackadder of that Ilk to the neighbouring Clan Home (pronounced "Hume").

[1] Andrew Blackadder followed the standard of Douglas at Flodden in 1513 and was slain along with two hundred gentlemen of that name on that disastrous field leaving a widow and two daughters, Beatrix and Margaret, who at the time were mere children.

The garrison refused to surrender but the Homes succeeded in obtaining possession of the fortress, seized the widow and her children, compelling them into forced marriages.

The two daughters were contracted to younger sons, John and Robert Home in 1518, and, as they were only in their eighth year, they were confined in the Castle of Blackadder until they came of age.

By 1567 the dispute had died down, as the Tulliallan branch and the Homes of Wedderburn were allies of Mary, Queen of Scots on the losing side in the important Battle of Carberry Hill.

[1] Some members of the clan continued to farm their lands as tenants of the Homes, and the last family burials at Edrom kirk were made in the 1980s.

[9] William Francis Blackadder played in the Scottish rugby team in 1938, and was awarded the DSO and OBE as an RAF ace in World War II.