Paraphrased from malazan.fandom.com
The continent of Lether was the setting for the novels Midnight Tides, Reaper’s Gale, Dust of Dreams, and The Crippled God. It lay on the other side of the globe from the Malazan Empire. The Letherii Empire, as a nation on Lether, believed in constant progress and expansion without end. They revered coin above all else. Intricate schemes and deadly sleight of hand were the lifeblood of the Letherii.
Kolanse was a region to the east of the continent of Lether, past the Wastelands and the Glass Desert. Estobanse Province, was the richest land of the Kolanse, thriving on springs. The southern kingdoms suffered from droughts, however. Several decades before the start of the Malazan Book of the Fallen, Kolanse had experienced a series of cyclically expansionist regimes which drove the tribes of Lether’s plains westward against the frontier of the Letherii Empire. Following a civil war, Kolanse retreated into isolation.