It is true at the end of this book we find mentioned Henricum regem tertium; but this is doubtless Henry II.
The above passage should further be compared with the survey of Caddington (1222): Dicunt juratores quod manerium istud defendit se versus regem pro x.
The above list will hopefully give you a few useful examples demonstrating the appropriate usage of "regem" in a variety of sentences. We hope that you will now be able to make sentences using this word.