What is the origin of the idiom "footloose and fancy-free" and when to use it?

The phrase "footloose and fancy-free" originated in the early 19th century. "Footloose" refers to being free to move or travel without being tied down or restricted, while "fancy-free" means having no attachments or commitments. It is often used to describe individuals who are not in a committed romantic relationship or have no other immediate obligations.