#151 - The Unconquered Standard of Arkhosia. Sure, it may have gotten lost when the empire fell, but the flag itself was never conquered!
#152 - A Dragonborn is the current favoured consort of Tiamat.
#153 - Dragonborn are "[d]eemed the choicest soldier's in Tiamat's armies".
#154 - The (unnamed) capital city of Arkhosia (a Dragonborn city, no less) ws the number one social location for metallic Dragons. If you weren't there, you were no-one.
Laurence J Sinclair