Adirondack Chairs!

Harry Bunnell's 1905 patented design (left) next to a later 1938 patent (right)

an Adirondack chair

While the Adirondacks themselves are relatively obscure and esoteric, Adirondack chairs are one of the most famous outdoor chairs in America.  I've always grown up around Adirondack chairs; while we didn't have them in my New York City apartment growing up, they were a mainstay in our Long Island beach house, and they were always noticeable to me when we travelled upstate.  I always loved these chairs because they were so big for my young tiny frame that I could cuddle up in them very comfortably.  I have taken this design of chair for granted, though, without knowing any of its history, other than that it was presumably created in the Adirondacks.

I was right about that part, at least.  Thomas Lee invented the Adirondack chair in 1903 in Westport, NY.  Westport is situated on the New York-side shore of Lake Champlain, within the "blue line" denoting the borders of the Adirondacks.  In Lee's futile search for cozy outdoor furniture that fit the aesthetic of his country-style cottage, he wound up frustrated and resorted to making his own.  Using only eleven pieces of wood from the same plank of wood, Lee designed multiple models and had his twenty-two family members test them out each individually.  Unsurprisingly, they chose the design of the modern Adirondack chair.  The chair sat low enough to be quite sturdy on uneven terrain and the high sloped back and wide armrests allowed for easy relaxation.
Lee's hunting partner Harry Bunnell was a carpenter, saw the chairs and immediately took to the design.  After asking Lee's permission, Bunnell began making the chairs and painting them green and dark brown, still two of the more popular and common Adirondack chair colors.  He began selling the chairs, and people bought them enthusiastically.  Without asking Lee, Bunnell filed for a patent in 1904 (no. 794,777) and named the design the Westport Plank Chair.  He carved his name into each chair he made, and now original Westport Plank Chairs with his name carved into their backs are sold for thousands of dollars.  Although Lee never gave permission for this, he also never sought to take legal action against Bunnell or stop Lee's profiting from the design.

Over time, all chairs of similar design (low-seated, high-backed, and with wide armrests) became known as Adirondack chairs.  The primary difference between the originals and most modern Adirondack chairs is the use of multiple smaller slabs of wood for the back, instead of the single plank that was first used.

a unique Adirondack chair

Sources:
http://www.apartmenttherapy.com/adirondack-chairs-quick-histor-118981
http://www.orvis.com/s/adirondack-chair-story-the-history-of-the-adirondack-chair/2978
http://dfohome.com/knowledge-center/patio-furniture/adirondack-chair-history