In this task you will be given a text passage from a trivia quiz. You should choose the category this question belongs to from these categories: History, Science, Social Science, Fine Arts, Literature. You can only choose one category, so if in doubt, please choose the closest match.

One commander at this battle was almost killed by Henry de Bohun while riding alone in front of his lines, but saved himself by killing Bohun with a battle axe. The defending army was drawn up into three squares, and a series of pits with stakes at the bottom was dug in front of their line. After the Earl of Gloucester was killed on the second day of fighting, it turned into a rout and the losing commander was forced to flee to Dunbar Castle. FTP, name this battle fought south of Stirling Castle in the summer of 1314, in which Edward II's army was defeated by Robert Bruce.
History

A maximum independent set for this data structure can be found in linear time by adding alternating levels. In this structure, any two vertices or nodes must be connected by a single simple path, and thus it is connected and acyclic. By using (*) union-find with disjoint sets, one type of this structure containing all the vertices of a connected graph can be constructed. One variety of this data structure can be used to easily implement a binary search. This structure also comes in red-black and self-balancing-binary varieties. For 10 points, identify this data structure from computer science, a hierarchical graph in which "leaf" nodes ultimately flow from a "root" node.
Science

The Franz Joseph and Fox Glaciers can be found in this nation, notable for existing at low altitudes. Its largest lake, found in the caldera of Mount Tauhara, is drained by the Waikato River and is called Lake Taupo. Its region known as the Canterbury Plains is found to the south of Christchurch, while its tallest mountain is Mount Cook. Also including the city of Auckland, the Cook Strait separates its two constituent islands, which are called North and South Island. For 10 points, Wellington is the capital of which island nation found east of Australia

Social Science