Douglas' father William Longleg was also Lord of Fawdon, and had as his superior Gilbert de Umfraville, Earl of Angus.

Douglas' father, Longleg died at some point c. 1274 and there is some confusion as to whether his eldest son Hugh predeceased him, however William le Hardi was certainly in possession of his estates by the end of the decade.

Douglas had married Elizabeth, daughter of Alexander Stewart, 4th High Steward of Scotland, by whom he had his eldest son James.

His imprisonment does not appear to have been unduly harsh, he was released by the spring of 1290 when his wife Eleanor posted bail for his release with four manucaptors in May 1290, these four knights, all her cousins, were John Hastings, 1st Baron Hastings, Nicholas de Segrave, 1st Baron Segrave, William de Rye and Robert Bardulf.

Whilst the negotiations were progressing, regarding the choice of the next King of Scots, Edward was staying with Sir Walter de Lindsay at Thurston Manor, near Innerwick, when William Douglas paid an oath of fealty to him in the chapel there.

Edward appointed his own baronial officers and made one Master Eustace de Bikerton, Parson of St Bride's Kirk, the spiritual home and burying ground of the Douglases.

In prison, Douglas was duty bound to be at his lands in Essex, in order to provide service for Edward, his failure cost him £20 sterling in fines.

These men concluded a treaty at Paris and ratified it at Dunfermline between the Kingdoms of Scotland, France and Norway, that would become known as the Auld Alliance[citation needed].

Appalled and after a resolute defence, the garrison of Berwick Castle under the leadership of William Douglas, gave themselves up to the mercy of King Edward.

The garrison were freed and were allowed to march out of the castle with their arms, but Douglas was imprisoned and the last of his estates in Essex forfeit.

He was the first nobleman to join with Sir William Wallace in 1297 in rebellion; combining forces at Sanquhar, Durisdeer and later Scone Abbey where the two liberated the English treasury.

Wallace joined his forces with that of Sir Andrew Moray and together they led the patriot army in the Battle at Stirling Bridge fought on 11 September 1297.

They were joined by other patriots such as Robert Wishart Bishop of Glasgow, and the Morays of Bothwell, with a contingent of Douglases at the national muster at Irvine, North Ayrshire.

When Edward heard of Douglas' supposed treason he commanded the future King of Scots Robert Bruce, Earl of Carrick, then governor of Carlisle for the English to take retribution.

[11] The third time Douglas was held a prisoner of King Edward, was after 9 July 1297 when he was accused by Sir Henry de Percy of breaking his covenant of peace with Edward that was agreed to in the document known as the Capitulation at Irving Water, where Douglas was in the company of Robert Brus, Alexander de Lindsay and John and James (the latter three his brothers in law).