Three things make The Empire great - faith, steel and gunpowder!

The Empire was founded by Sigmar of the Unberogen tribe, a very charismatic and powerful barbarian warlord.
Previously, the land was inhabited by many primitive tribes such as the Unberogen, Teutogens, Jeutones, Ungols and Bretoni. The tribes were often at war with one another, raiding for anything they needed or just to establish their power in the region. Sigmar's father Bjorn had already forged strong links with nearby tribes, but to unite the tribes under one banner was unprecedented and many feared it was an impossibility.
Establishing a powerful alliance with the Dwarfs, Sigmar began a quest to do exactly that. He travelled the Empire with his closest friends and his army, aiding tribal warlords in defense of their people and earning their trust. One by one, the leaders of the tribes pledged their support to Sigmar and the Unberogen.
Several tribes refused to join Sigmar, or were openly hostile and threatened open war with the Unberogen. The tribe of Bretoni decided to migrate to the west, eventually settling. These people, united in a similar way under the leader Gilles Le Breton, would eventually found the nation of Bretonnia. The Teutogens and their leader, Artur, and had terrorised neighbouring tribes, murdering and destroying. Artur believed in individual strength and the old ways of the tribes, and would not bow to any man.
Sigmar set out to challenge Artur. He climbed by hand to the top of the mighty rock Fauschlag, where the Teutogen camp lay, and fought Artur to the death. The Knights of the white wolf pledged from then on to serve Sigmar as his personal guard.
Having successfully earned the trust, respect and allegiance of the main tribes of the lands, Sigmar set out to Black Fire Pass, to await a massive greenskin horde that approached from the south. With aid from his allies the Dwarfs, and all of the tribes, Sigmar smashed the army, pushing the Greenskins back from the lands that would become the Empire ensuring security for many years to come.
Following the victory, Sigmar was crowned Emperor of the lands from the Worlds Edge mountains in the East, to Kislev in the north, The Black Mountains to the South and the Grey Mountains in the West. Alaric the Mad, a Dwarf runesmith, began to forge 12 great Runefangs for each of the tribal leaders that would become the Elector Counts. At this point, the Imperial Calendar begins, at year 1.

}{Imperial Family}{
Emperor: Karl Franz I
Prince:
Reiksmarshal Captain of the Reiksguard:

}{Royal Court}{
Elector Count of Reikland: Karl Franz I
Elector Count of Averland: Joseph I
Elector Count of Hochland:
Elector Count of Middenland:
Elector Count of Nordland:
Elector Count of Ostermark:
Elector Count of Ostland: Taisho
Elector Count of Stirland:
Elector Count of Talabecland:
Elector Count of Wissenland:
Count of the Moot:
Count of Altdorf: Darth Jadus
Count of Middenheim:
Count of Nuln:
Count of Talabheim:

Map of The Empire[whfb.lexicanum.com]
The Empire[whfb.lexicanum.com]
Warhammer World[whfb.lexicanum.com]