William Douglas of Nithsdale Sir William Douglas of Nithsdale ( c . 1370 – c . 1392 AD ) was a Scottish knight and Northern Crusader . Early life . William Douglas was an illegitimate son of Archibald the Grim , 3rd Earl of Douglas and an unknown mother . A man of apparently dashing bearing , Douglas was with the Franco - Scot s army when it unsuccessfully besieged Carlisle Castle in 1385 , the defending Governor being Lord Clifford . He is recorded as there performing feats of valour and killing many Englishmen . According to Andrew of Wyntoun : Marriage . Douglas certainly had gained his spurs by 1387 when he married Egidia ( or Gelis ) Stewart , princess of Scotland , a daughter of King Robert II . According to the Liber Pluscarden , Egidia Stewart ' s beauty was well renowned . Charles V of France had " sent a certain most subtle painter to do her portrait and portray her charms , intending to take her to wife . " But the King of France and all other of Egidia ' s admirers had lost out to the chivalric charms of Douglas . As part of her marriage portion went the lands of Nithsdale in south - western Scotland , Herbertshire in the county of Stirling and an annuity of £300 . Ireland . Within his first year of marriage the young Nithsdale led a punitive raid against Irish raiders who had been troubling the tenantry of his father ' s Fiefdom of Galloway . In early summer 1388 , with a party of 500 well prepared veteran men - at - arms he sailed into Carlingford Lough , landed outside the town and summoned their leaders . The chief of the townsfolk offered a sum for a temporary truce , to which Nithsdale agreed . Secretly the townsfolk sent off to Dundalk for reinforcements , with which they were obliged . 800 spearmen from Dundalk surprised the Scots camp by night , and were supported by a sortie from Carlingford town . The Scots , veterans of years of brutal Border warfare , drove the Irishmen off , captured the town and burnt it , seized the Castle and captured 15 ships in the harbour . " En route " back to Scotland Nithsdale " ravaged " the Isle of Man . Nithsdale ' s expeditionary force sailed back into Loch Ryan with enough time to participate in the raiding of Northern England that was to culminate in the Battle of Otterburn on 19 August , in which he fought with distinction . Feuding , Crusading and Death . The year after Otterburn a truce was called between Scotland and England . Nithsdale on a knightly quest for glory decided , about 1389 , to join the Teutonic Knights , who were fighting the Lithuanians in eastern Europe . Nithsdale had previously quarrelled with Lord Clifford , a former adversary at Carlisle and whose forebear had claimed Douglasdale under Edward I of England ' s oppression . While both were abroad , it is alleged that Clifford challenged Nithsdale to single combat , and that Douglas even went to France to obtain special armour for the fight . Clifford , however , died on 18 August 1391 , but Nithsdale is said to have kept their ' tryst ' , and whilst walking upon the bridge leading to the main gate at Danzig was " killed by the English " . The burghers of Danzig decided that " upon account of a signal service which the Douglas family did to this city in relieving it in its utmost extremities against the Poles , the Scotch were allowed to be free burghers of the town " . Subsequently the stone fascia of the Hohe Thor ( High Gate ) was adorned with the coat of arms of this nobleman and for centuries it was commonly referred to as the Douglas Port or Douglas Gate , described as such as late as 1734 . As Nithsdale had drawn most of his rentals from the burgh of Dumfries in 1392 his death is assumed to have occurred that year or shortly afterwards . Issue . By Princess Egidia , Nithsdale had two children :