The First Dragon War begins with the ogre and chromatic dragon invasion of Silvanesti and ends when the elves defeat the chromatic dragons.
known to dragons as the Elven War
The Third Dragon War ended with the defeat of an avatar of Takhisis by the knight Huma Dragonbane. Takhisis was banished from returning to the prime material plain. The Chromatic Dragons fled the continent. To keep the balance, the Metallic Dragons left the land. Soon people would forget dragons actually existing and instead consider these creatures nothing more than legend.
The War of the Lance was a continent spanning war involving the Dragonarmies, under the guidance of the Takhisis, the Queen of Darkness and goddess of evil. They were eventually opposed by the Whitestone Council (a collation of human, elven, and dwarven forces). For additional information, see The War of the Lance entry here.
Kitiara uth Matar and the remnants of the Dragonarmies that had almost conquered Ansalon during the The War of the Lance, laid siege to the city of Palanthas. She attacked the city utilizing a Flying Citadel. With Draconians raining down upon the streets, and Lord Soth and his Skeletal Warriors cutting a swath of destruction, the grand city fell to its knees.