"Such silver!" -King Silverbirch
King Silverbirch had a great obsession with silver, and he constantly pursued it up until his death. In his pursuit for more silver on the island, King Silverbirch treated his subjects mercilessly as he forced them to work in the mines, and many of them died, either from inhaling the fumes that came from the mine, from exhaustion, or from being killed for the inability or refusal to work.
He often had fits of anger, in which he would usually end up doing something he regretted later, such as sentence his subjects to death.
In Urchin and the Heartstone, he sends Lord Treeth, Bronze, Trail, and Scatter to Mistmantle Isle to kidnap Urchin, "The Marked Squirrel", with the hopes that Urchin could find more silver. Despite the protests of Smokewreath, King Silverbirch was very welcoming to Urchin, giving him food, water, and a nicely furnished room. Later, in a fit, he told Smokewreath that he could have Urchin when the first snowflake falls, and stripped Urchin's room. He also gave most of "the Freak's" care to Commander Cedar, who was still loyal to Queen Larch, and aided Urchin as often as possible.
After Urchin, Juniper, and Cedar fled Silverbirch's tower, the maniacal king sent guards, led by Granite, to catch them, and Urchin sacrificed himself to Smokewreath so they could go free. After Juniper freed them, there was an earthquake, which made the fortress collapse in on itself, killing Silverbirch and everyone else in the tower.