The Wars of Scottish Independence began in 1286 AD shortly after the d
eath of Scotland's king, Alexander III. Scotland's King Alexander III ruled for so long most of the reasons lower lords might fight one another disappeared. In a feudal political system, there's always a chance that ambition or competition could lead to war between the king and his vassals or between the vassals themselves. However, due to a combination of Alexander's positive personal qualities as a leader and the fact he lived for so long, Scotland enjoyed relative peace and security during his reign.
Immediately following the King's death, however, everything changed: Alexander left no son to succeed him as king. If he had had a son there could still be a period of uncertainty. Just being the eldest son of a king didn't mean you'd make a good leader; it also didn't mean that agreements made before the king died would necessarily be kept. Feudalism was, after all, a competitive top down political system, i.e. you frequently had to fight to keep your position and you needed allies (vassals) to be successful. If the king died and left no son to inherit the throne, then the closest male relatives of the king would assert their claim to be the next ruler. Rarely was the transition peaceful because even if your competition was more closely related, you could change all of that by defeating your opponent in war. If you won in battle, you won the crown. Ultimately, in the case of Alexander III, he left no son and so Scotland threatened to descend into civil war.
Scotland's situation was complicated for another reason: the nobles were divided in their loyalty. Many were as rich in English as they were in Scottish lands. To hold land in England one had to swear loyalty to England's King Edward I. Thus, the problem of dual-fealty unmistakably shaped Scotland's politics. This is because according to the rules of feudalism, if you served more than one lord you were obliged to first serve the seniormost lord. In this case, Edward I was senior to Alexander III. As it turned out, while Alexander III was alive the issue of dual fealty wasn't a problem. This is because the two kings got along well with one another; however, this reveals another problem with feudalism: things worked smoothly and peacefully if the lords liked one another. But the whole thing would come crashing down over a simple personality conflict or an insult. This obviously makes a feudal society much less stable, and not as long lasting, as a modern democratic society.
Once Alexander died Edward saw an opportunity to gain control over his northern neighbor. Due to the nature of feudalism and the feudal contract, Edward turned out to be the senior-most lord in Scotland. This meant he could select whomever he wanted to be the next Scottish king; but he had every intention of eventually absorbing Scotland into his own English kingdom.
SIGNING THE TREATY OF BIRGHAM
In 1286 AD, Alexander III died after falling from his horse. Before the accident Alexander believed he'd dealt with the problem of who would succeed him: he convinced the nobles of Scotland to let his four-year-old granddaughter (Margaret) to be Scotland's next queen.King Edward I of England had other plans. He refused to allow Scotland to be ruled by a queen. Edward forced his Scottish vassals to sign the Treaty of Birgham (1290 AD). The treaty placed into law that Margaret would marry Edward's son (the future Edward II of England). The Scots only agreed on condition Scotland would remain a separate kingdom from England.
In the end neither Alexander's or Edward's efforts mattered: Margaret died during the voyage from Norway to Scotland. Following her death rival lords from the Balliol and Bruce Clans began the struggle to decide who'd be the next king of Scotland.