He was a large raven, had a bird's-eyes view on everything, and was considered the most informed about the Great Desert and possible routes across it.
He was also considered the voice of wisdom in the council during the deliberations of Edmund, Susan and the Narnians who were held hostage to Rabadash's whim.
Like many an elder statesmen, he was inclined to use proverbs.
When Prince Rabadash decided to force Susan to marry him by keeping them all prisoner there, Sallowpad took part in the discussions and planning to escape.
It is most likely that he successfully escaped back to Narnia with the rest of his party.
Sallowpad also let Shasta know the way to Narnia across the desert.
His name, appropriate for a raven, means "yellow footed".