There's a few ideas involving how maine Coon cats arrived in America and received their name. 2 of the most common being linked to Marie Antoinette trying to escape France to Maine and another being Captain Charles Coon having these cats on his boat, where they would mate with feral cats in the air when he made port in New England.

You can find more here:
http://en.wikipedia.org/wiki/Maine_coon#Origin

The Maine Coon got its name through a series of myths and background history. This particular breed of cat has been around for quite some time, and one of the oldest pure breeds in America, "specifically native to Maine, where it is the official state cat."

Although genetically improbable a theory was proposed that the Main Coon "descended from semi-feral domestic cats and raccoons." Another myth that contributed to the "coon" being in the name was that of the story of Captain Charles Coon.

You can visit wikipedia to learn more of each story.

The Maine Coon is a breed of domestic cat well known for its distinctive physical appearance. It is one of the oldest natural breeds in North America, specifically native to the state of Maine,1 where it is the official State Cat.

Although the Maine Coon's exact origins and date of introduction to the United States are unknown, many theories have been proposed. The breed was popular in cat shows in the late 1800s, but its existence became threatened when long-haired breeds from overseas were introduced in the early 20th century. The Maine Coon has since made a comeback and is now the second most popular cat breed in North America, according to the Cat Fanciers' Association (CFA).

Their are two different stories about this for the most part... so bear with me. Marie Antoinette, the Queen of France, who was executed in 1793. Before her death, Antoinette attempted to escape France with the help of Captain Samuel Clough. She loaded Clough's ship with her most prized possessions, including six of her favorite long-haired cats. Although Antoinette did not make it to the United States, her pets safely reached the shores of Wiscasset, Maine, where they mated with short-haired breeds and evolved into the modern breed of the Maine Coon.

Another way describing how this happended involved Captain Charles Coon, an English seafarer who kept long-haired cats aboard his ships. Whenever Coon's ship would anchor in the New England ports, the felines would exit the ship and mate with the local feral cat population. When long-haired kittens began appearing in the litters of the local cat population, they were referred to as one of "Coon's cats".

For more information you can check out the website your self: http://en.wikipedia.org/wiki/Maine_Coon