These pieces of music would be perfect for after you've found out that you're heir to a foreign throne, and you're entering the royal palace.
Verdi, Aida, "Grand March." The Khedive of Egypt commissioned Verdi to compose the opera. My mom once saw a broadcast of it performed near the pyramids; she says it was a magical, majestic event.
Handel's Keyboard Suite in D Minor, 4th Movement, Sarabande. It was heavily influenced by "La Follia," one of the oldest pieces of European music.
Gilbert and Sullivan, The Mikado, "Behold the Lord High Executioner" & "As Someday It May Happen." The Mikado is one of my favorite operettas (topped only by The Pirates of Penzance!). You definitely want to sing the second song as you start dealing with your new subjects.
Ravel, "Boléro." Ravel thought of a factory when the music was played; I personally think of a grand procession taking place at the Alhambra. I love the bursts of flame in the video; André Rieu's performances are always so much fun to watch. His concert in Atlanta back in 2004 (?) was particularly fabulous.
Beethoven, 7th Symphony, 2nd Movement. This symphony premiered in 1813 for wounded soldiers; doesn't it just zing with the power and energy of the Napoleonic era? On a side note, it was used for the intro scene in "The Fall," a beautiful movie that everyone should see.
Handel, "Music for the Royal Fireworks." It celebrated the end of the War of the Austrian Succession, and was meant to be performed in conjunction with a display of fireworks in London.
"The Black Adder" theme. A must for all ne'er-do-well aspiring despots.
And of course -Arne, "Rule Britannia." The singer's coat is heinous, but the music exudes stateliness.