War of the Breton Succession(1365)

Party 1 (Blois) benefited from proximity to the French mainland for regular supplies and reinforcements, gaining an initial logistical edge. In contrast, Party 2 (Montfort) depended on maritime supply lines from England, which were frequently threatened by the French navy. However, in the later stages, the resilience of Montfort castles and the ability of English garrisons to live off local resources narrowed the sustainability gap.

Despite Charles of Blois being a capable commander, Party 1 suffered from fragmented command integrity due to interference from the French court and divided noble loyalties. Party 2 established a more flexible C2 structure through the joint efforts of Joan of Flanders and English commanders, especially with the initiative taken by subordinates like Sir Thomas Dagworth, which proved decisive.

Party 2 initially seized the advantage of time by quickly capturing Nantes, but this was negated by Party 1's counter-offensive. In later years, Montfort forces used Brittany's rugged terrain for hit-and-run tactics, withdrawing to castles to slow Blois armies. At the Battle of Auray, they chose the ground correctly to compress the enemy in a confined space.

Party 1 benefited from the French intelligence network to receive early warnings of English landings, but failed to gain sufficient insight into Montfort strongholds due to lack of local support. Party 2, with backing from western Breton populations, closely monitored enemy movements and, through the English spy network, stayed informed of political developments in France, gaining an edge in diplomatic maneuvers.

Party 2's English longbow and disciplined infantry provided decisive firepower superiority against heavily armored French knights at Auray. Party 1 relied on numerically superior cavalry, which proved ineffective in the rough terrain. In terms of morale, the Montfort independence narrative painted Blois as a 'French puppet,' giving Party 2 an advantage.