Brooke was senior knight of the shire when still in his twenties, taking precedence over his uncle, Sir Henry. As such he could have attended the subsidy committee appointed 11 Feb. 1589. Yet in 1593 he sat for Hedon. It is easier to account for his being returned for this small Yorkshire borough, perhaps through his brother-in-law Cecil, or through some link of his own family with the place (his uncle had represented it in 1555), than it is to account for his not representing a constituency in his own county. But in 1597 he was ‘beloved of never a man in Kent’ and it is interesting that in 1593 no member of his family sat for a Kent constituency. As Member of Parliament for Hedon he was appointed to committees on kerseys (23 Mar.) and the maintenance of weirs (28 Mar.).
Much is obscure about Cobham. Thus, in 1597, despite his unpopularity, he secured the lord lieutenancy and the wardenship of the Cinque Ports in the face of competition from the Sidneys, who were backed by the Earl of Essex. He took a less than heroic part in the Kent by-election campaign of January 1598, first claiming that he was ‘indifferent’ as to who stood for the vacancy when he was deeply involved in the underlying Ravenstone manor dispute; then, to the evident exasperation of his deputy lieutenant (Sir) John Leveson, suggesting for the vacancy a man who was already a Member.
