The basic roll-with-a-hole design is hundreds of years old and has other practical advantages besides providing for a more even cooking and baking of the dough: the hole could be used to thread string or dowels through groups of bagels, allowing for easier handling and transportation and more appealing seller displays. As one famously stated, Bagels are "Round food, for every mood!"
Contrary to common legend, the bagel was not created in the shape of a stirrup to commemorate the victory of Poland's King Jan III Sobieski over the Ottoman Turks in the Battle of Vienna in 1683. It was actually invented much earlier in Krakow, Poland, as a competitor to the obwarzanek, a lean bread of wheat flour designed for Lent. Leo Rosten wrote in "The Joys of Yiddish" about the first known mention of the word bajgiel in the "Community Regulations" of the city of Kraków in 1610, which stated that the item was given as a gift to women in childbirth. In the 16th and first half of the 17th centuries, the bajgiel became a staple of the Polish national diet and a staple of the Slavic diet generally.
That the name originated from beugal (old spelling of Bügel, meaning bail/bow or bale) is considered plausible by many, both from the similarities of the word and because traditional handmade bagels are not perfectly circular but rather slightly stirrup-shaped. (This, however, may be due to the way the boiled bagels are pressed together on the baking sheet before baking.)
The selling of bubliks and baranki would have been undertaken by a sbitenshchik. He would have been armed with strings and sticks, from which to hang his wares. This was a common way to sell these goods in the 19th century.
Additionally, variants of the word beugal are used in Yiddish and Austrian German to refer to a somewhat similar form of sweet filled pastry (Mohnbeugel (with poppy seeds) and Nussbeugel (with ground nuts)), or in southern German dialects (where beuge refers to a pile, e.g., holzbeuge, or woodpile). According to the Merriam-Webster's dictionary, 'bagel' derives from the transliteration of the Yiddish beygl', which came from the Middle High German böugel or ring, which itself came from bouc (ring) in Old High German, similar to the Old English bēag' (ring), and būgan' (to bend or bow). Similarly another etymology in the Webster's New World College Dictionary says that the Middle High German form was derived from the Austrian German beugel', a kind of croissant, and was similar to the German bügel', a stirrup or ring.
In the Brick Lane district and surrounding area of London, England, bagels, or as locally spelled "beigels", have been sold since the middle of the 19th century. They were often displayed in the windows of bakeries on vertical wooden dowels, up to a metre in length, on racks. This area is not to be confused with Pudding Lane, where the "Great Fire of London" started in 1666.
Bagels were brought to the US by immigrant Polish-Jews, with a thriving business developing in New York City that was controlled for decades by Bagel Bakers Local 338, which had contracts with nearly all bagel bakeries in and around the city for its workers, who prepared all their bagels by hand. In fact, to this day NYC is still famous for its high quality bagels.
The bagel came into more general use throughout North America in the last quarter of the 20th century, which was due at least partly to the efforts of bagel baker Harry Lender, his son, Murray Lender, and Florence Sender, who pioneered automated production and distribution of frozen bagels in the 1960s. Murray also invented pre-slicing the bagel. A clever man, by all accounts, for, as we all know, slicing bagels is seldom easy.
In modern times, Canadian-born astronaut Gregory Chamitoff is the first person known to have taken a batch of bagels into space on his 2008 Space Shuttle mission to the International Space Station. His shipment consisted of 18 sesame seed bagels.