The Crystalmist Mountains — the towering range that walls off the whole western edge of the Sheldomar Valley (the wider region Yeomanry sits in). This is giant country: hill giants, stone giants, and worse raid down out of these peaks regularly. Also home to orcs and other humanoid tribes.
Geoff — an isolated, fog-shrouded realm of herders, farmers, and miners (with a strong dwarf/gnome/elf presence) tucked against the mountains and the Rushmoors. Historically peaceful but constantly raided by giants coming out of the Crystalmists.
Sterich — a mineral-rich earldom next to the Jotens and Crystalmists, worked by dwarf and gnome clans. Like Geoff, it's a frontline against giant incursions — in fact, Sterich was actually overrun by giant and humanoid armies in the mid-580s CY and had to be reconquered with help from Keoland, Gran March, and the Ulek states.
The Valley of the Mage — a strange, isolated pocket deep in the Crystalmists/Barrier Peaks, ruled by a secretive, paranoid archmage and defended by gnomes and unusually tall elves.