1636 Robert Corbet II was sheriff. He was also Justice of the Peace and Custos Rotulorum of Shropshire and a master in Chancery.
1643 10 April, Robert Corbet was listed in a parliamentary paper as being one of many in Salop to be responsible for raising a force 'against Papists'. 'Whereas the Lords and Commons now in Parliament assembled, being certainly informed, that Papists and other wicked and illaffected persons, have traiterously combined together, and entred into an association, and have raised and daily doe raise great forces both of horse and foote, in severall Counties of this Kingdome, and have plundered, spoyled and destroyed multitudes of his Maiesties good Subiects, and if not timely prevented will utterly subvert and destroy the true Protestant Religion (which is their cheif designe) the Lawes of the land, the Priviledges of Parliament, and the liberty of the Subject'.
1654 Robert Corbet II was M.P. in the Commonwealth Parliament. Gough in his 'History of Myddle' writes "Under him I had my education for many years, and served him as a clerk. He was once chosen knight of the shire and served in parliament where they presented the Protector (Cromwell) with twenty four acts. He was willing to sign some of them but not all; but the parliament had voted that all should be signed or none. The Protector took time to consider until next day, and then he came to the parliament house with frowning countenance and with many opprobious terms dissolved them, and gave them the character of a pack of stubborn knaves."
Although Robert Corbet along with the Corbets of Adderley and of Auston near Pontesbury fought for the Parliament the head of the Corbet family, Sir Vincent, and his relative Pelham Corbet fought for the King.
Robert Corbet married Elizabeth the daughter of Sir Henry Ludlow of Clarington Park in Wiltshire and they had four sons the eldest being Thomas Corbet.