Welcome to Cipher Saturday!
You've found the home of everyone's favorite weekend pastime, where a stylized photo of a somewhat famous person from the past is provided for you to identify. If you want to see if your hunch is correct, you can type the person's name into Google Images and the real photo will appear on the first page of results.
So, who could I be? That's the mystery! Go ahead and take a guess and then go enjoy your day. Check back tomorrow and I'll reveal the answer. The first correct post will be declared the winner.
Additional clues may be found in the cipher below. Today you must use the key provided to unlock the king of all ciphers. Perhaps then you can meet the challenge.
The key is hidden in the image below (you may want to enlarge for better viewing):
PL F P SFMMBR NR PL F P SPFMT
ABOBMAS NM YNUR JFM, PMA TEB TPKBS TEBY OPFMT
PGGUSBA NC P SKPYFMD IBGPUSB F WPS EBPA
IUT GNUKAMT IB LB, PS F WPS FM IBA
GNMTFMUBA TEB TEFMD NVBR P SWFMB
PMA STPR-GRNSSBA KNVBRS NMB NC TEBL LFMB
PCTBR BMAFMD FT PKK FM NKA MFMBTY-NMB
F STPMA TPKK FM LPRIKB LY KFCB RPGB MNW RUM