Guy Fawkes, Guy,
Stick him up on high,
Hang him on a lamp post
And there let him die.

Guy Fawkes (1570-1606) was a convert to Roman Catholicism, and was mad at King James I for making harsh anti-catholic laws. He is the most famous member of the gunpowder plot, who planned to blow up the Palace of Westminster on November 5, 1605. Guy and six other conspirators were caught red-handed in the cellar of Westminster, and Guy was executed the following year.

Ladies and Gentlemen, you'll never grow fat
If you don't put a penny in the old Guy's hat.

Now Guy Fawkes day is celebrated every November 5th, and kids collect money (like Halloween, but with coins in place of candy) and make Guys, effigies of Guy Fawkes, to burn in bonfires. While Guy Fawkes day is not as big a deal as it once was, it is still widely celebrated in the UK.

Please to remember
The 5th of November
Gunfire treason and plot
I know no reason
Why gunpowder treason
Should ever be forgot