Dunsinane is located near Moray in Scotland. It was here that Demona massacred guards to steal food to feed her clan in 1020.  In 1032, she battled Gillecomgain to a standstill before the rising Sun cut the battle short. ("City of Stone Part One", "City of Stone Part Two")
Finally, in 1057, Demona led her clan, and Macbeth's army in a battle against Canmore and the English which ended in a stalemate. ("City of Stone Part Four")
Around the time Castle Moray was being attacked, Macbeth's cousin, Thorfinn was killed here. 
Real World Background
In William Shakespeare's Macbeth, the Weird Sisters prophesied that "Macbeth shall never vanquish'd be until / Great Birnam wood to high Dunsinane hill / Shall come against him." And later on, Malcolm leads an army, along with Macduff and Englishmen Siward (the Elder), the Earl of Northumberland, against Dunsinane Castle. While encamped in Birnam Wood, the soldiers are ordered to cut down and carry tree limbs to camouflage their numbers, thus fulfilling the Witches' third prophecy.
Greg Weisman originally intended to include a counterpart to the Birnam Wood scene in "City of Stone", but had to drop it for lack of room.