Attus Navius
Contrary to other divinatory practices present in Rome (e.g. haruspicina, consultation of the libri Sibyllini) augury appears to be autochthonous and originally Latin or Italic. The art has its roots in the prehistory of the Italic people and is attested in the Iguvine Tables (avif aseria) and among other Latin tribes. The very story or legend of the foundation of Rome is based on augury, i.e. the ascertaining of the will of gods through observation of the sky and of birds. Romulus and Remus indeed acted as augurs and Romulus was considered a great augur throughout the course of his life.
The character that best represented and portrayed the art however was Attus Navius. His story is related by Cicero. He was born into a very poor family. One day he lost one of his pigs. He then promised the gods that if he found it, he would offer them the biggest grapes growing in his vineyard. After recovering his pig he stood right at the middle of his grape yard facing South. He divided the sky into four sections and observed birds: when they appeared he walked in that direction and found an extraordinary large grape that he offered to the gods.
His story was immediately famous and he became the augur of the king (see above the episode with king Tarquinius narrated by Livy). Henceforth he was considered the patron of the augurs.
Read more about this topic: Augur