SAPPHIRE THRONE: Giants of Ages
1) The main continent of Serran is called Devania (aka "Known World). Devania is about 3000 miles wide and is home to kingdoms, villages, wildlands and ruins. The continent also has a large expansive Underdark, that spans the majority of the continent. The Underdark has several kingdoms of its own, populated by elves, gnomes, dwarves and even humans known as Vallorians.
2) The Empire of Tarsis and it's Holy Emperor are the secular and religious leader of the Known World. Although in recent years, the Empire's influence and sway has waned. He rules from the Holy Palace on a Lion -Guarded carved throne made of sapphire.
3) The world was ruled by giants and dragons. The old gods felt threatened by their power and struck down against the two forcing them to exist in smaller conclaves or as individuals scattered across the lands. The old gods then created the "small folk" (humans, dwarves etc) as the dominant races feeling they would be of little threat against them.
4) The world of Serran is not complete, several apertures exist that bleed into places such as the Feywild and Shadowfell and even other "known worlds". While travel is possible it is often dangerous.
5) After the Night of Dissolution, the Heroes of the Spire defeated the demi-god Kyuss, causing his essence to be cast on the winds. What was not ultimately destroyed, has created darkspawn creatures and magical nodes thus creating what is known as pact-magic used by warlocks and witches.