Q: Context: The newly appointed Prime Minister, William Pitt the Younger (portrayed by Simon Osborne as a petulant teenager), wants to declare war on Napoleon Bonaparte; give "tougher sentences" for his geography teacher "Banana-Breath" Scrigshanks; and, most of all, strike the idiotic Prince Regent from the Civil List. Despite hearing this, the Prince is nonetheless convinced that the general public adores him because yesterday, he heard them singing "We hail Prince George!", only to be corrected by his butler, Mr. Blackadder, as "We hate Prince George!" Since the House of Commons is evenly divided on the issue, Blackadder suggests to the Prince that they tip the scales in his favour by bribing a Member of Parliament (MP) named Sir Talbot Buxomley (Denis Lill) with the position of High Court judge. The Prince calls for Buxomley, who, after assuring the Prince that he will stand by him, promptly sits down in a chair and dies, due to his poor health.

Question: who played william pitt the younger in blackadder? Let's give stream of consciousness first:
The relevant information to answer the above question is: The newly appointed Prime Minister, William Pitt the Younger (portrayed by Simon Osborne as a petulant teenager), wants to declare war on Napoleon Bonaparte; give "tougher sentences" for his geography teacher "Banana-Breath" Scrigshanks; and, most of all, strike the idiotic Prince Regent from the Civil List. Therefore, the final answer is Simon Osborne.