An alliance between Duke Fushnina, Duke Malcik, and Duke Brandiss against Prince Jeremy of Halar. Jeremy decisively defeated them at the Battle of Grantin Field, and marked the occasion by crowning himself King of Dorland.
The armies of Prince Jeremy of Halar were assembled opposite the armies of Dukes Fushnina, Malcik, and Brandiss, as the War of the Three Dukes drew to its conclusion. Prince Jeremy naturally wanted to parlay and agreed to meet his adversaries in the middle first thing in the morning.
At that meeting, he requested that a neutral mediator be brought in for a last attempt at peace. Fushnina opposed this, as he and his men were ready to end things once and for all. Brandiss supported this, because of his strict sense of honor. So the deciding vote was given to Malcik . . . who after a few moments of deliberation agreed to wait for the mediator. This was largely because he had a higher opinion of Brandiss as a person than of Fushnina, who had been at odds with him throughout the campaign.
Precious hours were lost waiting for a priest not aligned with any party to arrive, and even more hours were lost as the parties ran in circles around each other. By the time the mediator left (realizing compromise wasn't possible,) it was too late to fight that day.
This was Halar's plan all along, of course - he'd made a secret alliance with another lord who had basically force marched his cavalry troops to the field, and that extra day for the men and horses to rest was vital. In the battle that followed the next day, the cavalry made all the difference - Fushnina was killed, Brandiss fled with the remnants of his forces, and Malcik was forced to accept the sovereignty of now King Jeremy.
If Duke Malcik had gone with what made sense from a strategic standpoint, rather than personal opinions, the Kingdom of Dorland would never have been established.
The War of the Three Dukes was started when an alliance of, yes, three dukes (Fushnina, Malcik, and Brandiss) decided that Prince Jeremy of Halar had ambitions to name himself high king of the Dors, and must be stopped. They sent their armies after him, hoping to depose him and divide his lands up among themselves.
They had initial success, but he refused to surrender or flee. After the first campaign season, he was able to reorganize his forces to strike back, making much better use of his greatmen than his opponents. He also actively sought out alliances with his neutral neighbors, finally gaining one with the "horse lord" Sir Donovan.
The armies met for the last time at Grantin Field - here Halar and his allies decisively defeated the Three Dukes; Fushnina was slain, Brandiss fled, and Malcik surrendered unconditionally. Prince Jeremy decided to have himself crowned king - not of all the Dors, but at least of the land he now controlled.
And thus the Kingdom of Dorland was born, the country in which most of my stories are set.
I think he'd be described by his contemporaries and successors as having "just the right amount of piety." He was concerned enough with the gods to make sure that his actions, both in private and in public, were pleasing to them; while, at the same time, not being the sort to start a crusade or give too much power to the priests, like some rulers might.
At the end of the War of the Three Dukes, Jeremy married his daughter to Duke Alvon of Fushnina, who replaced his father who had been killed in the final battle. Duchess Tirsa spent most of her time in the court of her father, helping him establish the kingdom, rather than with her husband the duke. She did bear him several children whenever she stopped by, but he spent most of his time with other women.
Tirsa's solution to this was generally to have the women and illegitimate children moved to the capital and given jobs in the royal court. This would keep them away from her husband and out of the line of succession, while making sure they were provided for. This was seen as almost unheard of generosity for a woman in her position, who'd either ignore her husband's mistresses or leave them to starve.