The History of Snoopy:

Snoopy is a loyal, imaginative, and good-natured beagle who is prone to imagining fantasy lives, including being an author, a college student known as "Joe Cool", an attorney, and a British World War I flying ace. He is perhaps best known in this last persona, wearing an aviator's helmet and goggles and a scarf while carrying a swagger stick (like a stereotypical British Army officer of World War I and II)

Snoopy appeared on October 4, 1950, two days after the first Peanuts strip. He was originally Patty's dog^[10] before being adopted by Charlie Brown.^[11] He was called Snoopy for the first time in the November 10th strip. On March 16, 1952,^[12] his thoughts were first shown in a thought balloon. Snoopy first appeared upright on his hind legs on January 9, 1956, when he was shown sliding across a sheet of ice after Shermy and Lucy had first done so.^[13]

Snoopy appeared as a character balloon in the Macy's Thanksgiving Day Parade in 1968; the balloon depicted Snoopy in his World War I Flying Ace costume

That  is just history of Snoopy. Starting a dog series.. Good Luck Happy Geocaching