Prior to the 19th century, hunting was an all day affair where the enjoyment was derived from the chase rather than the kill. Beagles are scent hounds developed primarily for hunting hare in this setting--an activity known as beagling. Because of their excellent scent-tracking skills and stamina, beagles were almost guaranteed to catch the hare eventually--but unlike Harriers, they did not finish the hunt too quickly.

The white tip, known as the flag, was bred for selectively, as the tail remains easily seen when the dog's head is down following a scent.

Although the origin of the word "beagle" is uncertain, it has been suggested that it might derive from the French word begueule, meaning "open throat"; or the French word beugler, meaning "to bellow"; or the German word begele, meaning "to scold." They all would make perfect sense as the beagle is known for its distinctive voice.

The modern breed was developed in Great Britain around the 1830s from several breeds, including the Talbot Hound, the North Country Beagle, the Southern Hound, and possibly the Harrier.

Queen Elizabeth I kept a breed known as a Pocket Beagle, which stood 8 to 9 inches (20 to 23 cm) at the shoulder. Small enough to fit in a "pocket" or saddlebag, they rode along on the hunt. The larger hounds would run the prey to ground, then the hunters would release the small dogs to continue the chase through underbrush.

Unlike humans who have only 5 million scent receptors, Beagles have about 220 million. Because of this, Beagles are commonly used in security and law enforcement to track prohibited or illegal materials at crime scenes and airports.

The general appearance of the beagle resembles a miniature Foxhound, but the head is broader and the muzzle shorter, the expression completely different, and the legs shorter in proportion to the body.

Snoopy is an anthropomorphic beagle in the comic strip Peanuts by Charles M. Schulz. He is loyal, imaginative, good-natured, and 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. One of the most recognizable and iconic characters in comic strips worldwide, Snoopy is considered more famous than his owner Charlie Brown in some countries.

The puggle was first bred by designer dog breeders in the United States with the aim of producing a healthy companion dog that was less likely to inherit a number of serious health issues common in the pug, particularly breathing issues associated with the breed's brachycephalic head, and also less likely to inherit the energy, scent drive, and howl of the beagle--but due to the unpredictable nature of crossing two established breeds, puggles can still inherit both breathing disorders and high energy levels.

Reverend Phillip Honeywood established a beagle pack in Essex in the 1830s and it is believed that this pack formed the basis for the modern breed.