Oscar Wilde 
The Ballad of Reading Gaol 

Classic poem, written in jail. According to Wikipedia: 'Oscar Fingal O’Flahertie Wills Wilde (1854 – 1900) was an Irish playwright, novelist, poet, and author of short stories. Known for his barbed wit, he was one of the most successful playwrights of late Victorian London, and one of the greatest celebrities of his day. As the result of a famous trial, he suffered a dramatic downfall and was imprisoned for two years of hard labour after being convicted of the offence of 'gross indecency.”